rocksdb/utilities/backupable/backupable_db.cc

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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#ifndef ROCKSDB_LITE
#include "rocksdb/utilities/backupable_db.h"
#include <stdlib.h>
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
#include <algorithm>
#include <atomic>
#include <cinttypes>
#include <functional>
#include <future>
#include <limits>
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
#include <map>
#include <mutex>
#include <sstream>
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
#include <string>
#include <thread>
#include <unordered_map>
#include <unordered_set>
#include <vector>
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
Introduce a new storage specific Env API (#5761) Summary: The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc. This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO. The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before. This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection. The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761 Differential Revision: D18868376 Pulled By: anand1976 fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 23:47:08 +01:00
#include "env/composite_env_wrapper.h"
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
#include "file/filename.h"
#include "file/sequence_file_reader.h"
#include "file/writable_file_writer.h"
#include "logging/logging.h"
#include "port/port.h"
#include "rocksdb/rate_limiter.h"
#include "rocksdb/transaction_log.h"
#include "table/sst_file_dumper.h"
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
#include "test_util/sync_point.h"
#include "util/channel.h"
#include "util/coding.h"
#include "util/crc32c.h"
#include "util/string_util.h"
#include "utilities/checkpoint/checkpoint_impl.h"
namespace ROCKSDB_NAMESPACE {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
namespace {
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
using ShareFilesNaming = BackupableDBOptions::ShareFilesNaming;
inline uint32_t ChecksumHexToInt32(const std::string& checksum_hex) {
std::string checksum_str;
Slice(checksum_hex).DecodeHex(&checksum_str);
return EndianSwapValue(DecodeFixed32(checksum_str.c_str()));
}
inline std::string ChecksumStrToHex(const std::string& checksum_str) {
return Slice(checksum_str).ToString(true);
}
inline std::string ChecksumInt32ToHex(const uint32_t& checksum_value) {
std::string checksum_str;
PutFixed32(&checksum_str, EndianSwapValue(checksum_value));
return ChecksumStrToHex(checksum_str);
}
} // namespace
void BackupStatistics::IncrementNumberSuccessBackup() {
number_success_backup++;
}
void BackupStatistics::IncrementNumberFailBackup() {
number_fail_backup++;
}
uint32_t BackupStatistics::GetNumberSuccessBackup() const {
return number_success_backup;
}
uint32_t BackupStatistics::GetNumberFailBackup() const {
return number_fail_backup;
}
std::string BackupStatistics::ToString() const {
char result[50];
snprintf(result, sizeof(result), "# success backup: %u, # fail backup: %u",
GetNumberSuccessBackup(), GetNumberFailBackup());
return result;
}
void BackupableDBOptions::Dump(Logger* logger) const {
ROCKS_LOG_INFO(logger, " Options.backup_dir: %s",
backup_dir.c_str());
ROCKS_LOG_INFO(logger, " Options.backup_env: %p", backup_env);
ROCKS_LOG_INFO(logger, " Options.share_table_files: %d",
static_cast<int>(share_table_files));
ROCKS_LOG_INFO(logger, " Options.info_log: %p", info_log);
ROCKS_LOG_INFO(logger, " Options.sync: %d",
static_cast<int>(sync));
ROCKS_LOG_INFO(logger, " Options.destroy_old_data: %d",
static_cast<int>(destroy_old_data));
ROCKS_LOG_INFO(logger, " Options.backup_log_files: %d",
static_cast<int>(backup_log_files));
ROCKS_LOG_INFO(logger, " Options.backup_rate_limit: %" PRIu64,
backup_rate_limit);
ROCKS_LOG_INFO(logger, " Options.restore_rate_limit: %" PRIu64,
restore_rate_limit);
ROCKS_LOG_INFO(logger, "Options.max_background_operations: %d",
max_background_operations);
}
// -------- BackupEngineImpl class ---------
class BackupEngineImpl : public BackupEngine {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
public:
BackupEngineImpl(const BackupableDBOptions& options, Env* db_env,
bool read_only = false);
~BackupEngineImpl() override;
using BackupEngine::CreateNewBackupWithMetadata;
Status CreateNewBackupWithMetadata(const CreateBackupOptions& options, DB* db,
const std::string& app_metadata) override;
Status PurgeOldBackups(uint32_t num_backups_to_keep) override;
Status DeleteBackup(BackupID backup_id) override;
void StopBackup() override {
stop_backup_.store(true, std::memory_order_release);
}
Status GarbageCollect() override;
// The returned BackupInfos are in chronological order, which means the
// latest backup comes last.
void GetBackupInfo(std::vector<BackupInfo>* backup_info) override;
void GetCorruptedBackups(std::vector<BackupID>* corrupt_backup_ids) override;
using BackupEngine::RestoreDBFromBackup;
Status RestoreDBFromBackup(const RestoreOptions& options, BackupID backup_id,
const std::string& db_dir,
const std::string& wal_dir) override;
using BackupEngine::RestoreDBFromLatestBackup;
Status RestoreDBFromLatestBackup(const RestoreOptions& options,
const std::string& db_dir,
const std::string& wal_dir) override {
return RestoreDBFromBackup(options, latest_valid_backup_id_, db_dir,
wal_dir);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
Status VerifyBackup(BackupID backup_id,
bool verify_with_checksum = false) override;
Status Initialize();
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
ShareFilesNaming GetNamingNoFlags() const {
return options_.share_files_with_checksum_naming &
BackupableDBOptions::kMaskNoNamingFlags;
}
ShareFilesNaming GetNamingFlags() const {
return options_.share_files_with_checksum_naming &
BackupableDBOptions::kMaskNamingFlags;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
private:
void DeleteChildren(const std::string& dir, uint32_t file_type_filter = 0);
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
Status DeleteBackupInternal(BackupID backup_id);
// Extends the "result" map with pathname->size mappings for the contents of
// "dir" in "env". Pathnames are prefixed with "dir".
Status InsertPathnameToSizeBytes(
const std::string& dir, Env* env,
std::unordered_map<std::string, uint64_t>* result);
struct FileInfo {
FileInfo(const std::string& fname, uint64_t sz, const std::string& checksum,
const std::string& id = "", const std::string& sid = "")
: refs(0),
filename(fname),
size(sz),
checksum_hex(checksum),
db_id(id),
db_session_id(sid) {}
FileInfo(const FileInfo&) = delete;
FileInfo& operator=(const FileInfo&) = delete;
int refs;
const std::string filename;
const uint64_t size;
const std::string checksum_hex;
// DB identities
// db_id is obtained for potential usage in the future but not used
// currently
const std::string db_id;
// db_session_id appears in the backup SST filename if the table naming
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
// option is kUseDbSessionId
const std::string db_session_id;
};
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
class BackupMeta {
public:
BackupMeta(
const std::string& meta_filename, const std::string& meta_tmp_filename,
std::unordered_map<std::string, std::shared_ptr<FileInfo>>* file_infos,
Env* env)
: timestamp_(0),
sequence_number_(0),
size_(0),
meta_filename_(meta_filename),
meta_tmp_filename_(meta_tmp_filename),
file_infos_(file_infos),
env_(env) {}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
BackupMeta(const BackupMeta&) = delete;
BackupMeta& operator=(const BackupMeta&) = delete;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
~BackupMeta() {}
void RecordTimestamp() {
env_->GetCurrentTime(&timestamp_);
}
int64_t GetTimestamp() const {
return timestamp_;
}
uint64_t GetSize() const {
return size_;
}
uint32_t GetNumberFiles() { return static_cast<uint32_t>(files_.size()); }
void SetSequenceNumber(uint64_t sequence_number) {
sequence_number_ = sequence_number;
}
uint64_t GetSequenceNumber() {
return sequence_number_;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
const std::string& GetAppMetadata() const { return app_metadata_; }
void SetAppMetadata(const std::string& app_metadata) {
app_metadata_ = app_metadata;
}
Status AddFile(std::shared_ptr<FileInfo> file_info);
Status Delete(bool delete_meta = true);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
bool Empty() {
return files_.empty();
}
std::shared_ptr<FileInfo> GetFile(const std::string& filename) const {
auto it = file_infos_->find(filename);
if (it == file_infos_->end())
return nullptr;
return it->second;
}
const std::vector<std::shared_ptr<FileInfo>>& GetFiles() {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return files_;
}
// @param abs_path_to_size Pre-fetched file sizes (bytes).
Status LoadFromFile(
const std::string& backup_dir,
const std::unordered_map<std::string, uint64_t>& abs_path_to_size);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
Status StoreToFile(bool sync);
std::string GetInfoString() {
std::ostringstream ss;
ss << "Timestamp: " << timestamp_ << std::endl;
char human_size[16];
AppendHumanBytes(size_, human_size, sizeof(human_size));
ss << "Size: " << human_size << std::endl;
ss << "Files:" << std::endl;
for (const auto& file : files_) {
AppendHumanBytes(file->size, human_size, sizeof(human_size));
ss << file->filename << ", size " << human_size << ", refs "
<< file->refs << std::endl;
}
return ss.str();
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
private:
int64_t timestamp_;
// sequence number is only approximate, should not be used
// by clients
uint64_t sequence_number_;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
uint64_t size_;
std::string app_metadata_;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
std::string const meta_filename_;
std::string const meta_tmp_filename_;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// files with relative paths (without "/" prefix!!)
std::vector<std::shared_ptr<FileInfo>> files_;
std::unordered_map<std::string, std::shared_ptr<FileInfo>>* file_infos_;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
Env* env_;
static const size_t max_backup_meta_file_size_ = 10 * 1024 * 1024; // 10MB
}; // BackupMeta
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
inline std::string GetAbsolutePath(
const std::string &relative_path = "") const {
assert(relative_path.size() == 0 || relative_path[0] != '/');
return options_.backup_dir + "/" + relative_path;
}
inline std::string GetPrivateDirRel() const {
return "private";
}
inline std::string GetSharedDirRel() const { return "shared"; }
inline std::string GetSharedChecksumDirRel() const {
return "shared_checksum";
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
inline std::string GetPrivateFileRel(BackupID backup_id,
bool tmp = false,
const std::string& file = "") const {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
assert(file.size() == 0 || file[0] != '/');
return GetPrivateDirRel() + "/" + ROCKSDB_NAMESPACE::ToString(backup_id) +
(tmp ? ".tmp" : "") + "/" + file;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
inline std::string GetSharedFileRel(const std::string& file = "",
bool tmp = false) const {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
assert(file.size() == 0 || file[0] != '/');
return GetSharedDirRel() + "/" + (tmp ? "." : "") + file +
(tmp ? ".tmp" : "");
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
inline std::string GetSharedFileWithChecksumRel(const std::string& file = "",
bool tmp = false) const {
assert(file.size() == 0 || file[0] != '/');
return GetSharedChecksumDirRel() + "/" + (tmp ? "." : "") + file +
(tmp ? ".tmp" : "");
}
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
inline bool UseLegacyNaming(const std::string& sid) const {
return GetNamingNoFlags() ==
BackupableDBOptions::kLegacyCrc32cAndFileSize ||
sid.empty();
}
inline bool UseInterimNaming(const std::string& sid) const {
// The indicator of SST file from early internal 6.12 release
// is a '-' in the DB session id. DB session id was made more
// concise without '-' after that.
return (GetNamingFlags() & BackupableDBOptions::kFlagMatchInterimNaming) &&
sid.find('-') != std::string::npos;
}
inline std::string GetSharedFileWithChecksum(
const std::string& file, bool has_checksum,
const std::string& checksum_hex, const uint64_t file_size,
const std::string& db_session_id) const {
assert(file.size() == 0 || file[0] != '/');
std::string file_copy = file;
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
if (UseLegacyNaming(db_session_id)) {
assert(has_checksum);
(void)has_checksum;
file_copy.insert(file_copy.find_last_of('.'),
"_" + ToString(ChecksumHexToInt32(checksum_hex)) + "_" +
ToString(file_size));
} else if (UseInterimNaming(db_session_id)) {
file_copy.insert(file_copy.find_last_of('.'), "_" + db_session_id);
} else {
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
file_copy.insert(file_copy.find_last_of('.'), "_s" + db_session_id);
if (GetNamingFlags() & BackupableDBOptions::kFlagIncludeFileSize) {
file_copy.insert(file_copy.find_last_of('.'),
"_" + ToString(file_size));
}
}
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
return file_copy;
}
inline std::string GetFileFromChecksumFile(const std::string& file) const {
assert(file.size() == 0 || file[0] != '/');
std::string file_copy = file;
size_t first_underscore = file_copy.find_first_of('_');
return file_copy.erase(first_underscore,
file_copy.find_last_of('.') - first_underscore);
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
inline std::string GetBackupMetaDir() const {
return GetAbsolutePath("meta");
}
inline std::string GetBackupMetaFile(BackupID backup_id, bool tmp) const {
return GetBackupMetaDir() + "/" + (tmp ? "." : "") +
ROCKSDB_NAMESPACE::ToString(backup_id) + (tmp ? ".tmp" : "");
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
// If size_limit == 0, there is no size limit, copy everything.
//
// Exactly one of src and contents must be non-empty.
//
// @param src If non-empty, the file is copied from this pathname.
// @param contents If non-empty, the file will be created with these contents.
Status CopyOrCreateFile(const std::string& src, const std::string& dst,
const std::string& contents, Env* src_env,
Env* dst_env, const EnvOptions& src_env_options,
bool sync, RateLimiter* rate_limiter,
uint64_t* size = nullptr,
std::string* checksum_hex = nullptr,
uint64_t size_limit = 0,
std::function<void()> progress_callback = []() {});
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
Status ReadFileAndComputeChecksum(const std::string& src, Env* src_env,
const EnvOptions& src_env_options,
uint64_t size_limit,
std::string* checksum_hex);
// Obtain db_id and db_session_id from the table properties of file_path
Status GetFileDbIdentities(Env* src_env, const EnvOptions& src_env_options,
const std::string& file_path, std::string* db_id,
std::string* db_session_id);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
struct CopyOrCreateResult {
uint64_t size;
std::string checksum_hex;
std::string db_id;
std::string db_session_id;
Status status;
};
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
// Exactly one of src_path and contents must be non-empty. If src_path is
// non-empty, the file is copied from this pathname. Otherwise, if contents is
// non-empty, the file will be created at dst_path with these contents.
struct CopyOrCreateWorkItem {
std::string src_path;
std::string dst_path;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::string contents;
Env* src_env;
Env* dst_env;
EnvOptions src_env_options;
bool sync;
RateLimiter* rate_limiter;
uint64_t size_limit;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::promise<CopyOrCreateResult> result;
std::function<void()> progress_callback;
bool verify_checksum_after_work;
std::string src_checksum_func_name;
std::string src_checksum_hex;
std::string db_id;
std::string db_session_id;
utilities/backupable : Fix coverity issues Summary: 1. Class BackupMeta ``` 52 : timestamp_(0), size_(0), meta_filename_(meta_filename), CID 1168103 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member sequence_number_ is not initialized in this constructor nor in any functions that it calls. 153 file_infos_(file_infos), env_(env) {} ``` 2. class BackupEngineImpl ``` 513 } 7. uninit_member: Non-static class member latest_backup_id_ is not initialized in this constructor nor in any functions that it calls. CID 1322803 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 9. uninit_member: Non-static class member latest_valid_backup_id_ is not initialized in this constructor nor in any functions that it calls. 514} ``` 3. struct BackupAfterCopyOrCreateWorkItem ``` 368 struct BackupAfterCopyOrCreateWorkItem { 369 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for shared. 370 bool shared; 3. member_decl: Class member declaration for needed_to_copy. 371 bool needed_to_copy; 5. member_decl: Class member declaration for backup_env. 372 Env* backup_env; 373 std::string dst_path_tmp; 374 std::string dst_path; 375 std::string dst_relative; 2. uninit_member: Non-static class member shared is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member needed_to_copy is not initialized in this constructor nor in any functions that it calls. CID 1396122 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 6. uninit_member: Non-static class member backup_env is not initialized in this constructor nor in any functions that it calls. 376 BackupAfterCopyOrCreateWorkItem() {} ``` 4. struct CopyOrCreateWorkItem ``` 318 struct CopyOrCreateWorkItem { 319 std::string src_path; 320 std::string dst_path; 321 std::string contents; 1. member_decl: Class member declaration for src_env. 322 Env* src_env; 3. member_decl: Class member declaration for dst_env. 323 Env* dst_env; 5. member_decl: Class member declaration for sync. 324 bool sync; 7. member_decl: Class member declaration for rate_limiter. 325 RateLimiter* rate_limiter; 9. member_decl: Class member declaration for size_limit. 326 uint64_t size_limit; 327 std::promise<CopyOrCreateResult> result; 328 std::function<void()> progress_callback; 329 2. uninit_member: Non-static class member src_env is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member dst_env is not initialized in this constructor nor in any functions that it calls. 6. uninit_member: Non-static class member sync is not initialized in this constructor nor in any functions that it calls. 8. uninit_member: Non-static class member rate_limiter is not initialized in this constructor nor in any functions that it calls. CID 1396123 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 10. uninit_member: Non-static class member size_limit is not initialized in this constructor nor in any functions that it calls. 330 CopyOrCreateWorkItem() {} ``` 5. struct RestoreAfterCopyOrCreateWorkItem ``` struct RestoreAfterCopyOrCreateWorkItem { 410 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for checksum_value. 411 uint32_t checksum_value; CID 1396153 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member checksum_value is not initialized in this constructor nor in any functions that it calls. 412 RestoreAfterCopyOrCreateWorkItem() {} ``` Closes https://github.com/facebook/rocksdb/pull/3131 Differential Revision: D6428556 Pulled By: sagar0 fbshipit-source-id: a86675444543eff028e3cae6942197a143a112c4
2017-11-28 23:31:46 +01:00
CopyOrCreateWorkItem()
: src_path(""),
dst_path(""),
contents(""),
src_env(nullptr),
dst_env(nullptr),
src_env_options(),
sync(false),
rate_limiter(nullptr),
size_limit(0),
verify_checksum_after_work(false),
src_checksum_func_name(kUnknownFileChecksumFuncName),
src_checksum_hex(""),
db_id(""),
db_session_id("") {}
utilities/backupable : Fix coverity issues Summary: 1. Class BackupMeta ``` 52 : timestamp_(0), size_(0), meta_filename_(meta_filename), CID 1168103 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member sequence_number_ is not initialized in this constructor nor in any functions that it calls. 153 file_infos_(file_infos), env_(env) {} ``` 2. class BackupEngineImpl ``` 513 } 7. uninit_member: Non-static class member latest_backup_id_ is not initialized in this constructor nor in any functions that it calls. CID 1322803 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 9. uninit_member: Non-static class member latest_valid_backup_id_ is not initialized in this constructor nor in any functions that it calls. 514} ``` 3. struct BackupAfterCopyOrCreateWorkItem ``` 368 struct BackupAfterCopyOrCreateWorkItem { 369 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for shared. 370 bool shared; 3. member_decl: Class member declaration for needed_to_copy. 371 bool needed_to_copy; 5. member_decl: Class member declaration for backup_env. 372 Env* backup_env; 373 std::string dst_path_tmp; 374 std::string dst_path; 375 std::string dst_relative; 2. uninit_member: Non-static class member shared is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member needed_to_copy is not initialized in this constructor nor in any functions that it calls. CID 1396122 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 6. uninit_member: Non-static class member backup_env is not initialized in this constructor nor in any functions that it calls. 376 BackupAfterCopyOrCreateWorkItem() {} ``` 4. struct CopyOrCreateWorkItem ``` 318 struct CopyOrCreateWorkItem { 319 std::string src_path; 320 std::string dst_path; 321 std::string contents; 1. member_decl: Class member declaration for src_env. 322 Env* src_env; 3. member_decl: Class member declaration for dst_env. 323 Env* dst_env; 5. member_decl: Class member declaration for sync. 324 bool sync; 7. member_decl: Class member declaration for rate_limiter. 325 RateLimiter* rate_limiter; 9. member_decl: Class member declaration for size_limit. 326 uint64_t size_limit; 327 std::promise<CopyOrCreateResult> result; 328 std::function<void()> progress_callback; 329 2. uninit_member: Non-static class member src_env is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member dst_env is not initialized in this constructor nor in any functions that it calls. 6. uninit_member: Non-static class member sync is not initialized in this constructor nor in any functions that it calls. 8. uninit_member: Non-static class member rate_limiter is not initialized in this constructor nor in any functions that it calls. CID 1396123 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 10. uninit_member: Non-static class member size_limit is not initialized in this constructor nor in any functions that it calls. 330 CopyOrCreateWorkItem() {} ``` 5. struct RestoreAfterCopyOrCreateWorkItem ``` struct RestoreAfterCopyOrCreateWorkItem { 410 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for checksum_value. 411 uint32_t checksum_value; CID 1396153 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member checksum_value is not initialized in this constructor nor in any functions that it calls. 412 RestoreAfterCopyOrCreateWorkItem() {} ``` Closes https://github.com/facebook/rocksdb/pull/3131 Differential Revision: D6428556 Pulled By: sagar0 fbshipit-source-id: a86675444543eff028e3cae6942197a143a112c4
2017-11-28 23:31:46 +01:00
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
CopyOrCreateWorkItem(const CopyOrCreateWorkItem&) = delete;
CopyOrCreateWorkItem& operator=(const CopyOrCreateWorkItem&) = delete;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
CopyOrCreateWorkItem(CopyOrCreateWorkItem&& o) ROCKSDB_NOEXCEPT {
*this = std::move(o);
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
CopyOrCreateWorkItem& operator=(CopyOrCreateWorkItem&& o) ROCKSDB_NOEXCEPT {
src_path = std::move(o.src_path);
dst_path = std::move(o.dst_path);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
contents = std::move(o.contents);
src_env = o.src_env;
dst_env = o.dst_env;
src_env_options = std::move(o.src_env_options);
sync = o.sync;
rate_limiter = o.rate_limiter;
size_limit = o.size_limit;
result = std::move(o.result);
progress_callback = std::move(o.progress_callback);
verify_checksum_after_work = o.verify_checksum_after_work;
src_checksum_func_name = std::move(o.src_checksum_func_name);
src_checksum_hex = std::move(o.src_checksum_hex);
db_id = std::move(o.db_id);
db_session_id = std::move(o.db_session_id);
return *this;
}
CopyOrCreateWorkItem(
std::string _src_path, std::string _dst_path, std::string _contents,
Env* _src_env, Env* _dst_env, EnvOptions _src_env_options, bool _sync,
RateLimiter* _rate_limiter, uint64_t _size_limit,
std::function<void()> _progress_callback = []() {},
bool _verify_checksum_after_work = false,
const std::string& _src_checksum_func_name =
kUnknownFileChecksumFuncName,
const std::string& _src_checksum_hex = "",
const std::string& _db_id = "", const std::string& _db_session_id = "")
: src_path(std::move(_src_path)),
dst_path(std::move(_dst_path)),
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
contents(std::move(_contents)),
src_env(_src_env),
dst_env(_dst_env),
src_env_options(std::move(_src_env_options)),
sync(_sync),
rate_limiter(_rate_limiter),
size_limit(_size_limit),
progress_callback(_progress_callback),
verify_checksum_after_work(_verify_checksum_after_work),
src_checksum_func_name(_src_checksum_func_name),
src_checksum_hex(_src_checksum_hex),
db_id(_db_id),
db_session_id(_db_session_id) {}
};
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
struct BackupAfterCopyOrCreateWorkItem {
std::future<CopyOrCreateResult> result;
bool shared;
bool needed_to_copy;
Env* backup_env;
std::string dst_path_tmp;
std::string dst_path;
std::string dst_relative;
utilities/backupable : Fix coverity issues Summary: 1. Class BackupMeta ``` 52 : timestamp_(0), size_(0), meta_filename_(meta_filename), CID 1168103 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member sequence_number_ is not initialized in this constructor nor in any functions that it calls. 153 file_infos_(file_infos), env_(env) {} ``` 2. class BackupEngineImpl ``` 513 } 7. uninit_member: Non-static class member latest_backup_id_ is not initialized in this constructor nor in any functions that it calls. CID 1322803 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 9. uninit_member: Non-static class member latest_valid_backup_id_ is not initialized in this constructor nor in any functions that it calls. 514} ``` 3. struct BackupAfterCopyOrCreateWorkItem ``` 368 struct BackupAfterCopyOrCreateWorkItem { 369 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for shared. 370 bool shared; 3. member_decl: Class member declaration for needed_to_copy. 371 bool needed_to_copy; 5. member_decl: Class member declaration for backup_env. 372 Env* backup_env; 373 std::string dst_path_tmp; 374 std::string dst_path; 375 std::string dst_relative; 2. uninit_member: Non-static class member shared is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member needed_to_copy is not initialized in this constructor nor in any functions that it calls. CID 1396122 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 6. uninit_member: Non-static class member backup_env is not initialized in this constructor nor in any functions that it calls. 376 BackupAfterCopyOrCreateWorkItem() {} ``` 4. struct CopyOrCreateWorkItem ``` 318 struct CopyOrCreateWorkItem { 319 std::string src_path; 320 std::string dst_path; 321 std::string contents; 1. member_decl: Class member declaration for src_env. 322 Env* src_env; 3. member_decl: Class member declaration for dst_env. 323 Env* dst_env; 5. member_decl: Class member declaration for sync. 324 bool sync; 7. member_decl: Class member declaration for rate_limiter. 325 RateLimiter* rate_limiter; 9. member_decl: Class member declaration for size_limit. 326 uint64_t size_limit; 327 std::promise<CopyOrCreateResult> result; 328 std::function<void()> progress_callback; 329 2. uninit_member: Non-static class member src_env is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member dst_env is not initialized in this constructor nor in any functions that it calls. 6. uninit_member: Non-static class member sync is not initialized in this constructor nor in any functions that it calls. 8. uninit_member: Non-static class member rate_limiter is not initialized in this constructor nor in any functions that it calls. CID 1396123 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 10. uninit_member: Non-static class member size_limit is not initialized in this constructor nor in any functions that it calls. 330 CopyOrCreateWorkItem() {} ``` 5. struct RestoreAfterCopyOrCreateWorkItem ``` struct RestoreAfterCopyOrCreateWorkItem { 410 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for checksum_value. 411 uint32_t checksum_value; CID 1396153 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member checksum_value is not initialized in this constructor nor in any functions that it calls. 412 RestoreAfterCopyOrCreateWorkItem() {} ``` Closes https://github.com/facebook/rocksdb/pull/3131 Differential Revision: D6428556 Pulled By: sagar0 fbshipit-source-id: a86675444543eff028e3cae6942197a143a112c4
2017-11-28 23:31:46 +01:00
BackupAfterCopyOrCreateWorkItem()
: shared(false),
needed_to_copy(false),
backup_env(nullptr),
dst_path_tmp(""),
dst_path(""),
dst_relative("") {}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
BackupAfterCopyOrCreateWorkItem(BackupAfterCopyOrCreateWorkItem&& o)
ROCKSDB_NOEXCEPT {
*this = std::move(o);
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
BackupAfterCopyOrCreateWorkItem& operator=(
BackupAfterCopyOrCreateWorkItem&& o) ROCKSDB_NOEXCEPT {
result = std::move(o.result);
shared = o.shared;
needed_to_copy = o.needed_to_copy;
backup_env = o.backup_env;
dst_path_tmp = std::move(o.dst_path_tmp);
dst_path = std::move(o.dst_path);
dst_relative = std::move(o.dst_relative);
return *this;
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
BackupAfterCopyOrCreateWorkItem(std::future<CopyOrCreateResult>&& _result,
bool _shared, bool _needed_to_copy,
Env* _backup_env, std::string _dst_path_tmp,
std::string _dst_path,
std::string _dst_relative)
: result(std::move(_result)),
shared(_shared),
needed_to_copy(_needed_to_copy),
backup_env(_backup_env),
dst_path_tmp(std::move(_dst_path_tmp)),
dst_path(std::move(_dst_path)),
dst_relative(std::move(_dst_relative)) {}
};
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
struct RestoreAfterCopyOrCreateWorkItem {
std::future<CopyOrCreateResult> result;
std::string checksum_hex;
RestoreAfterCopyOrCreateWorkItem() : checksum_hex("") {}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
RestoreAfterCopyOrCreateWorkItem(std::future<CopyOrCreateResult>&& _result,
const std::string& _checksum_hex)
: result(std::move(_result)), checksum_hex(_checksum_hex) {}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
RestoreAfterCopyOrCreateWorkItem(RestoreAfterCopyOrCreateWorkItem&& o)
ROCKSDB_NOEXCEPT {
*this = std::move(o);
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
RestoreAfterCopyOrCreateWorkItem& operator=(
RestoreAfterCopyOrCreateWorkItem&& o) ROCKSDB_NOEXCEPT {
result = std::move(o.result);
checksum_hex = std::move(o.checksum_hex);
return *this;
}
};
bool initialized_;
std::mutex byte_report_mutex_;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
channel<CopyOrCreateWorkItem> files_to_copy_or_create_;
std::vector<port::Thread> threads_;
std::atomic<CpuPriority> threads_cpu_priority_;
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
// Certain operations like PurgeOldBackups and DeleteBackup will trigger
// automatic GarbageCollect (true) unless we've already done one in this
// session and have not failed to delete backup files since then (false).
bool might_need_garbage_collect_ = true;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
// Adds a file to the backup work queue to be copied or created if it doesn't
// already exist.
//
// Exactly one of src_dir and contents must be non-empty.
//
// @param src_dir If non-empty, the file in this directory named fname will be
// copied.
// @param fname Name of destination file and, in case of copy, source file.
// @param contents If non-empty, the file will be created with these contents.
Status AddBackupFileWorkItem(
std::unordered_set<std::string>& live_dst_paths,
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::vector<BackupAfterCopyOrCreateWorkItem>& backup_items_to_finish,
BackupID backup_id, bool shared, const std::string& src_dir,
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
const std::string& fname, // starts with "/"
const EnvOptions& src_env_options, RateLimiter* rate_limiter,
uint64_t size_bytes, uint64_t size_limit = 0,
bool shared_checksum = false,
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::function<void()> progress_callback = []() {},
const std::string& contents = std::string(),
const std::string& src_checksum_func_name = kUnknownFileChecksumFuncName,
const std::string& src_checksum_str = kUnknownFileChecksum);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// backup state data
BackupID latest_backup_id_;
BackupID latest_valid_backup_id_;
std::map<BackupID, std::unique_ptr<BackupMeta>> backups_;
std::map<BackupID, std::pair<Status, std::unique_ptr<BackupMeta>>>
corrupt_backups_;
std::unordered_map<std::string,
std::shared_ptr<FileInfo>> backuped_file_infos_;
std::atomic<bool> stop_backup_;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// options data
BackupableDBOptions options_;
Env* db_env_;
Env* backup_env_;
// directories
std::unique_ptr<Directory> backup_directory_;
std::unique_ptr<Directory> shared_directory_;
std::unique_ptr<Directory> meta_directory_;
std::unique_ptr<Directory> private_directory_;
static const size_t kDefaultCopyFileBufferSize = 5 * 1024 * 1024LL; // 5MB
size_t copy_file_buffer_size_;
bool read_only_;
BackupStatistics backup_statistics_;
static const size_t kMaxAppMetaSize = 1024 * 1024; // 1MB
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
};
Status BackupEngine::Open(const BackupableDBOptions& options, Env* env,
BackupEngine** backup_engine_ptr) {
std::unique_ptr<BackupEngineImpl> backup_engine(
new BackupEngineImpl(options, env));
auto s = backup_engine->Initialize();
if (!s.ok()) {
*backup_engine_ptr = nullptr;
return s;
}
*backup_engine_ptr = backup_engine.release();
return Status::OK();
}
BackupEngineImpl::BackupEngineImpl(const BackupableDBOptions& options,
Env* db_env, bool read_only)
: initialized_(false),
threads_cpu_priority_(),
utilities/backupable : Fix coverity issues Summary: 1. Class BackupMeta ``` 52 : timestamp_(0), size_(0), meta_filename_(meta_filename), CID 1168103 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member sequence_number_ is not initialized in this constructor nor in any functions that it calls. 153 file_infos_(file_infos), env_(env) {} ``` 2. class BackupEngineImpl ``` 513 } 7. uninit_member: Non-static class member latest_backup_id_ is not initialized in this constructor nor in any functions that it calls. CID 1322803 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 9. uninit_member: Non-static class member latest_valid_backup_id_ is not initialized in this constructor nor in any functions that it calls. 514} ``` 3. struct BackupAfterCopyOrCreateWorkItem ``` 368 struct BackupAfterCopyOrCreateWorkItem { 369 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for shared. 370 bool shared; 3. member_decl: Class member declaration for needed_to_copy. 371 bool needed_to_copy; 5. member_decl: Class member declaration for backup_env. 372 Env* backup_env; 373 std::string dst_path_tmp; 374 std::string dst_path; 375 std::string dst_relative; 2. uninit_member: Non-static class member shared is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member needed_to_copy is not initialized in this constructor nor in any functions that it calls. CID 1396122 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 6. uninit_member: Non-static class member backup_env is not initialized in this constructor nor in any functions that it calls. 376 BackupAfterCopyOrCreateWorkItem() {} ``` 4. struct CopyOrCreateWorkItem ``` 318 struct CopyOrCreateWorkItem { 319 std::string src_path; 320 std::string dst_path; 321 std::string contents; 1. member_decl: Class member declaration for src_env. 322 Env* src_env; 3. member_decl: Class member declaration for dst_env. 323 Env* dst_env; 5. member_decl: Class member declaration for sync. 324 bool sync; 7. member_decl: Class member declaration for rate_limiter. 325 RateLimiter* rate_limiter; 9. member_decl: Class member declaration for size_limit. 326 uint64_t size_limit; 327 std::promise<CopyOrCreateResult> result; 328 std::function<void()> progress_callback; 329 2. uninit_member: Non-static class member src_env is not initialized in this constructor nor in any functions that it calls. 4. uninit_member: Non-static class member dst_env is not initialized in this constructor nor in any functions that it calls. 6. uninit_member: Non-static class member sync is not initialized in this constructor nor in any functions that it calls. 8. uninit_member: Non-static class member rate_limiter is not initialized in this constructor nor in any functions that it calls. CID 1396123 (#1 of 1): Uninitialized pointer field (UNINIT_CTOR) 10. uninit_member: Non-static class member size_limit is not initialized in this constructor nor in any functions that it calls. 330 CopyOrCreateWorkItem() {} ``` 5. struct RestoreAfterCopyOrCreateWorkItem ``` struct RestoreAfterCopyOrCreateWorkItem { 410 std::future<CopyOrCreateResult> result; 1. member_decl: Class member declaration for checksum_value. 411 uint32_t checksum_value; CID 1396153 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR) 2. uninit_member: Non-static class member checksum_value is not initialized in this constructor nor in any functions that it calls. 412 RestoreAfterCopyOrCreateWorkItem() {} ``` Closes https://github.com/facebook/rocksdb/pull/3131 Differential Revision: D6428556 Pulled By: sagar0 fbshipit-source-id: a86675444543eff028e3cae6942197a143a112c4
2017-11-28 23:31:46 +01:00
latest_backup_id_(0),
latest_valid_backup_id_(0),
stop_backup_(false),
options_(options),
db_env_(db_env),
backup_env_(options.backup_env != nullptr ? options.backup_env : db_env_),
copy_file_buffer_size_(kDefaultCopyFileBufferSize),
read_only_(read_only) {
if (options_.backup_rate_limiter == nullptr &&
options_.backup_rate_limit > 0) {
options_.backup_rate_limiter.reset(
NewGenericRateLimiter(options_.backup_rate_limit));
}
if (options_.restore_rate_limiter == nullptr &&
options_.restore_rate_limit > 0) {
options_.restore_rate_limiter.reset(
NewGenericRateLimiter(options_.restore_rate_limit));
}
}
BackupEngineImpl::~BackupEngineImpl() {
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
files_to_copy_or_create_.sendEof();
for (auto& t : threads_) {
t.join();
}
LogFlush(options_.info_log);
}
Status BackupEngineImpl::Initialize() {
assert(!initialized_);
initialized_ = true;
if (read_only_) {
ROCKS_LOG_INFO(options_.info_log, "Starting read_only backup engine");
}
options_.Dump(options_.info_log);
if (!read_only_) {
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
// we might need to clean up from previous crash or I/O errors
might_need_garbage_collect_ = true;
if (options_.max_valid_backups_to_open != port::kMaxInt32) {
options_.max_valid_backups_to_open = port::kMaxInt32;
ROCKS_LOG_WARN(
options_.info_log,
"`max_valid_backups_to_open` is not set to the default value. Ignoring "
"its value since BackupEngine is not read-only.");
}
// gather the list of directories that we need to create
std::vector<std::pair<std::string, std::unique_ptr<Directory>*>>
directories;
directories.emplace_back(GetAbsolutePath(), &backup_directory_);
if (options_.share_table_files) {
if (options_.share_files_with_checksum) {
directories.emplace_back(
GetAbsolutePath(GetSharedFileWithChecksumRel()),
&shared_directory_);
} else {
directories.emplace_back(GetAbsolutePath(GetSharedFileRel()),
&shared_directory_);
}
}
directories.emplace_back(GetAbsolutePath(GetPrivateDirRel()),
&private_directory_);
directories.emplace_back(GetBackupMetaDir(), &meta_directory_);
// create all the dirs we need
for (const auto& d : directories) {
auto s = backup_env_->CreateDirIfMissing(d.first);
if (s.ok()) {
s = backup_env_->NewDirectory(d.first, d.second);
}
if (!s.ok()) {
return s;
}
}
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
std::vector<std::string> backup_meta_files;
{
auto s = backup_env_->GetChildren(GetBackupMetaDir(), &backup_meta_files);
if (s.IsNotFound()) {
return Status::NotFound(GetBackupMetaDir() + " is missing");
} else if (!s.ok()) {
return s;
}
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// create backups_ structure
for (auto& file : backup_meta_files) {
if (file == "." || file == "..") {
continue;
}
ROCKS_LOG_INFO(options_.info_log, "Detected backup %s", file.c_str());
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
BackupID backup_id = 0;
sscanf(file.c_str(), "%u", &backup_id);
if (backup_id == 0 || file != ROCKSDB_NAMESPACE::ToString(backup_id)) {
if (!read_only_) {
// invalid file name, delete that
auto s = backup_env_->DeleteFile(GetBackupMetaDir() + "/" + file);
ROCKS_LOG_INFO(options_.info_log,
"Unrecognized meta file %s, deleting -- %s",
file.c_str(), s.ToString().c_str());
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
continue;
}
assert(backups_.find(backup_id) == backups_.end());
// Insert all the (backup_id, BackupMeta) that will be loaded later
// The loading performed later will check whether there are corrupt backups
// and move the corrupt backups to corrupt_backups_
backups_.insert(std::make_pair(
backup_id, std::unique_ptr<BackupMeta>(new BackupMeta(
GetBackupMetaFile(backup_id, false /* tmp */),
GetBackupMetaFile(backup_id, true /* tmp */),
&backuped_file_infos_, backup_env_))));
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
latest_backup_id_ = 0;
latest_valid_backup_id_ = 0;
2015-04-25 11:14:27 +02:00
if (options_.destroy_old_data) { // Destroy old data
assert(!read_only_);
ROCKS_LOG_INFO(
options_.info_log,
"Backup Engine started with destroy_old_data == true, deleting all "
"backups");
auto s = PurgeOldBackups(0);
if (s.ok()) {
s = GarbageCollect();
}
if (!s.ok()) {
return s;
}
} else { // Load data from storage
// abs_path_to_size: maps absolute paths of files in backup directory to
// their corresponding sizes
std::unordered_map<std::string, uint64_t> abs_path_to_size;
// Insert files and their sizes in backup sub-directories (shared and
// shared_checksum) to abs_path_to_size
for (const auto& rel_dir :
{GetSharedFileRel(), GetSharedFileWithChecksumRel()}) {
const auto abs_dir = GetAbsolutePath(rel_dir);
InsertPathnameToSizeBytes(abs_dir, backup_env_, &abs_path_to_size);
}
// load the backups if any, until valid_backups_to_open of the latest
// non-corrupted backups have been successfully opened.
int valid_backups_to_open = options_.max_valid_backups_to_open;
for (auto backup_iter = backups_.rbegin();
backup_iter != backups_.rend();
++backup_iter) {
assert(latest_backup_id_ == 0 || latest_backup_id_ > backup_iter->first);
if (latest_backup_id_ == 0) {
latest_backup_id_ = backup_iter->first;
}
if (valid_backups_to_open == 0) {
break;
}
// Insert files and their sizes in backup sub-directories
// (private/backup_id) to abs_path_to_size
InsertPathnameToSizeBytes(
GetAbsolutePath(GetPrivateFileRel(backup_iter->first)), backup_env_,
&abs_path_to_size);
Status s = backup_iter->second->LoadFromFile(options_.backup_dir,
abs_path_to_size);
if (s.IsCorruption()) {
ROCKS_LOG_INFO(options_.info_log, "Backup %u corrupted -- %s",
backup_iter->first, s.ToString().c_str());
corrupt_backups_.insert(
std::make_pair(backup_iter->first,
std::make_pair(s, std::move(backup_iter->second))));
} else if (!s.ok()) {
// Distinguish corruption errors from errors in the backup Env.
// Errors in the backup Env (i.e., this code path) will cause Open() to
// fail, whereas corruption errors would not cause Open() failures.
return s;
} else {
ROCKS_LOG_INFO(options_.info_log, "Loading backup %" PRIu32 " OK:\n%s",
backup_iter->first,
backup_iter->second->GetInfoString().c_str());
assert(latest_valid_backup_id_ == 0 ||
latest_valid_backup_id_ > backup_iter->first);
if (latest_valid_backup_id_ == 0) {
latest_valid_backup_id_ = backup_iter->first;
}
--valid_backups_to_open;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
}
for (const auto& corrupt : corrupt_backups_) {
backups_.erase(backups_.find(corrupt.first));
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
// erase the backups before max_valid_backups_to_open
int num_unopened_backups;
if (options_.max_valid_backups_to_open == 0) {
num_unopened_backups = 0;
} else {
num_unopened_backups =
std::max(0, static_cast<int>(backups_.size()) -
options_.max_valid_backups_to_open);
}
for (int i = 0; i < num_unopened_backups; ++i) {
assert(backups_.begin()->second->Empty());
backups_.erase(backups_.begin());
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
ROCKS_LOG_INFO(options_.info_log, "Latest backup is %u", latest_backup_id_);
ROCKS_LOG_INFO(options_.info_log, "Latest valid backup is %u",
latest_valid_backup_id_);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
// set up threads perform copies from files_to_copy_or_create_ in the
// background
threads_cpu_priority_ = CpuPriority::kNormal;
threads_.reserve(options_.max_background_operations);
for (int t = 0; t < options_.max_background_operations; t++) {
threads_.emplace_back([this]() {
#if defined(_GNU_SOURCE) && defined(__GLIBC_PREREQ)
#if __GLIBC_PREREQ(2, 12)
pthread_setname_np(pthread_self(), "backup_engine");
#endif
#endif
CpuPriority current_priority = CpuPriority::kNormal;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
CopyOrCreateWorkItem work_item;
while (files_to_copy_or_create_.read(work_item)) {
CpuPriority priority = threads_cpu_priority_;
if (current_priority != priority) {
TEST_SYNC_POINT_CALLBACK(
"BackupEngineImpl::Initialize:SetCpuPriority", &priority);
port::SetCpuPriority(0, priority);
current_priority = priority;
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
CopyOrCreateResult result;
result.status = CopyOrCreateFile(
work_item.src_path, work_item.dst_path, work_item.contents,
work_item.src_env, work_item.dst_env, work_item.src_env_options,
work_item.sync, work_item.rate_limiter, &result.size,
&result.checksum_hex, work_item.size_limit,
work_item.progress_callback);
result.db_id = work_item.db_id;
result.db_session_id = work_item.db_session_id;
if (result.status.ok() && work_item.verify_checksum_after_work) {
// unknown checksum function name implies no db table file checksum in
// db manifest; work_item.verify_checksum_after_work being true means
// backup engine has calculated its crc32c checksum for the table
// file; therefore, we are able to compare the checksums.
if (work_item.src_checksum_func_name ==
kUnknownFileChecksumFuncName ||
work_item.src_checksum_func_name == kDbFileChecksumFuncName) {
if (work_item.src_checksum_hex != result.checksum_hex) {
std::string checksum_info(
"Expected checksum is " + work_item.src_checksum_hex +
" while computed checksum is " + result.checksum_hex);
result.status =
Status::Corruption("Checksum mismatch after copying to " +
work_item.dst_path + ": " + checksum_info);
}
} else {
std::string checksum_function_info(
"Existing checksum function is " +
work_item.src_checksum_func_name +
" while provided checksum function is " +
kBackupFileChecksumFuncName);
ROCKS_LOG_INFO(
options_.info_log,
"Unable to verify checksum after copying to %s: %s\n",
work_item.dst_path.c_str(), checksum_function_info.c_str());
}
}
work_item.result.set_value(std::move(result));
}
});
}
ROCKS_LOG_INFO(options_.info_log, "Initialized BackupEngine");
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return Status::OK();
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
Status BackupEngineImpl::CreateNewBackupWithMetadata(
const CreateBackupOptions& options, DB* db,
const std::string& app_metadata) {
assert(initialized_);
assert(!read_only_);
if (app_metadata.size() > kMaxAppMetaSize) {
return Status::InvalidArgument("App metadata too large");
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (options.decrease_background_thread_cpu_priority) {
if (options.background_thread_cpu_priority < threads_cpu_priority_) {
threads_cpu_priority_.store(options.background_thread_cpu_priority);
}
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
BackupID new_backup_id = latest_backup_id_ + 1;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
assert(backups_.find(new_backup_id) == backups_.end());
auto private_dir = GetAbsolutePath(GetPrivateFileRel(new_backup_id));
Status s = backup_env_->FileExists(private_dir);
if (s.ok()) {
// maybe last backup failed and left partial state behind, clean it up.
// need to do this before updating backups_ such that a private dir
More fixes to auto-GarbageCollect in BackupEngine (#6023) Summary: Production: * Fixes GarbageCollect (and auto-GC triggered by PurgeOldBackups, DeleteBackup, or CreateNewBackup) to clean up backup directory independent of current settings (except max_valid_backups_to_open; see issue https://github.com/facebook/rocksdb/issues/4997) and prior settings used with same backup directory. * Fixes GarbageCollect (and auto-GC) not to attempt to remove "." and ".." entries from directories. * Clarifies contract with users in modifying BackupEngine operations. In short, leftovers from any incomplete operation are cleaned up by any subsequent call to that same kind of operation (PurgeOldBackups and DeleteBackup considered the same kind of operation). GarbageCollect is available to clean up after all kinds. (NB: right now PurgeOldBackups and DeleteBackup will clean up after incomplete CreateNewBackup, but we aren't promising to continue that behavior.) Pull Request resolved: https://github.com/facebook/rocksdb/pull/6023 Test Plan: * Refactors open parameters to use an option enum, for readability, etc. (Also fixes an unused parameter bug in the redundant OpenDBAndBackupEngineShareWithChecksum.) * Fixes an apparent bug in ShareTableFilesWithChecksumsTransition in which old backup data was destroyed in the transition to be tested. That test is now augmented to ensure GarbageCollect (or auto-GC) does not remove shared files when BackupEngine is opened with share_table_files=false. * Augments DeleteTmpFiles test to ensure that CreateNewBackup does auto-GC when an incompletely created backup is detected. Differential Revision: D18453559 Pulled By: pdillinger fbshipit-source-id: 5e54e7b08d711b161bc9c656181012b69a8feac4
2019-11-14 15:18:23 +01:00
// named after new_backup_id will be cleaned up.
// (If an incomplete new backup is followed by an incomplete delete
// of the latest full backup, then there could be more than one next
// id with a private dir, the last thing to be deleted in delete
// backup, but all will be cleaned up with a GarbageCollect.)
s = GarbageCollect();
} else if (s.IsNotFound()) {
// normal case, the new backup's private dir doesn't exist yet
s = Status::OK();
}
auto ret = backups_.insert(std::make_pair(
new_backup_id, std::unique_ptr<BackupMeta>(new BackupMeta(
GetBackupMetaFile(new_backup_id, false /* tmp */),
GetBackupMetaFile(new_backup_id, true /* tmp */),
&backuped_file_infos_, backup_env_))));
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
assert(ret.second == true);
auto& new_backup = ret.first->second;
new_backup->RecordTimestamp();
new_backup->SetAppMetadata(app_metadata);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
auto start_backup = backup_env_->NowMicros();
ROCKS_LOG_INFO(options_.info_log,
"Started the backup process -- creating backup %u",
new_backup_id);
if (s.ok()) {
s = backup_env_->CreateDir(private_dir);
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
RateLimiter* rate_limiter = options_.backup_rate_limiter.get();
if (rate_limiter) {
copy_file_buffer_size_ = static_cast<size_t>(rate_limiter->GetSingleBurstBytes());
}
// A set into which we will insert the dst_paths that are calculated for live
// files and live WAL files.
// This is used to check whether a live files shares a dst_path with another
// live file.
std::unordered_set<std::string> live_dst_paths;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::vector<BackupAfterCopyOrCreateWorkItem> backup_items_to_finish;
// Add a CopyOrCreateWorkItem to the channel for each live file
db->DisableFileDeletions();
if (s.ok()) {
CheckpointImpl checkpoint(db);
uint64_t sequence_number = 0;
DBOptions db_options = db->GetDBOptions();
FileChecksumGenFactory* db_checksum_factory =
db_options.file_checksum_gen_factory.get();
const std::string kFileChecksumGenFactoryName =
"FileChecksumGenCrc32cFactory";
bool compare_checksum =
db_checksum_factory != nullptr &&
db_checksum_factory->Name() == kFileChecksumGenFactoryName
? true
: false;
EnvOptions src_raw_env_options(db_options);
s = checkpoint.CreateCustomCheckpoint(
db_options,
[&](const std::string& /*src_dirname*/, const std::string& /*fname*/,
FileType) {
// custom checkpoint will switch to calling copy_file_cb after it sees
// NotSupported returned from link_file_cb.
return Status::NotSupported();
} /* link_file_cb */,
[&](const std::string& src_dirname, const std::string& fname,
uint64_t size_limit_bytes, FileType type,
const std::string& checksum_func_name,
const std::string& checksum_val) {
if (type == kWalFile && !options_.backup_log_files) {
return Status::OK();
}
Log(options_.info_log, "add file for backup %s", fname.c_str());
uint64_t size_bytes = 0;
Status st;
if (type == kTableFile) {
st = db_env_->GetFileSize(src_dirname + fname, &size_bytes);
}
EnvOptions src_env_options;
switch (type) {
case kWalFile:
src_env_options =
db_env_->OptimizeForLogRead(src_raw_env_options);
break;
case kTableFile:
src_env_options = db_env_->OptimizeForCompactionTableRead(
src_raw_env_options, ImmutableDBOptions(db_options));
break;
case kDescriptorFile:
src_env_options =
db_env_->OptimizeForManifestRead(src_raw_env_options);
break;
default:
// Other backed up files (like options file) are not read by live
// DB, so don't need to worry about avoiding mixing buffered and
// direct I/O. Just use plain defaults.
src_env_options = src_raw_env_options;
break;
}
if (st.ok()) {
st = AddBackupFileWorkItem(
live_dst_paths, backup_items_to_finish, new_backup_id,
options_.share_table_files && type == kTableFile, src_dirname,
fname, src_env_options, rate_limiter, size_bytes,
size_limit_bytes,
options_.share_files_with_checksum && type == kTableFile,
options.progress_callback, "" /* contents */,
checksum_func_name, checksum_val);
}
return st;
} /* copy_file_cb */,
[&](const std::string& fname, const std::string& contents, FileType) {
Log(options_.info_log, "add file for backup %s", fname.c_str());
return AddBackupFileWorkItem(
live_dst_paths, backup_items_to_finish, new_backup_id,
false /* shared */, "" /* src_dir */, fname,
EnvOptions() /* src_env_options */, rate_limiter, contents.size(),
0 /* size_limit */, false /* shared_checksum */,
options.progress_callback, contents);
} /* create_file_cb */,
&sequence_number, options.flush_before_backup ? 0 : port::kMaxUint64,
compare_checksum);
if (s.ok()) {
new_backup->SetSequenceNumber(sequence_number);
}
}
ROCKS_LOG_INFO(options_.info_log, "add files for backup done, wait finish.");
Status item_status;
for (auto& item : backup_items_to_finish) {
item.result.wait();
auto result = item.result.get();
item_status = result.status;
if (item_status.ok() && item.shared && item.needed_to_copy) {
item_status =
item.backup_env->RenameFile(item.dst_path_tmp, item.dst_path);
}
if (item_status.ok()) {
item_status = new_backup.get()->AddFile(std::make_shared<FileInfo>(
item.dst_relative, result.size, result.checksum_hex, result.db_id,
result.db_session_id));
}
if (!item_status.ok()) {
s = item_status;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
}
// we copied all the files, enable file deletions
db->EnableFileDeletions(false);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
auto backup_time = backup_env_->NowMicros() - start_backup;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (s.ok()) {
// persist the backup metadata on the disk
s = new_backup->StoreToFile(options_.sync);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
if (s.ok() && options_.sync) {
std::unique_ptr<Directory> backup_private_directory;
backup_env_->NewDirectory(
GetAbsolutePath(GetPrivateFileRel(new_backup_id, false)),
&backup_private_directory);
if (backup_private_directory != nullptr) {
s = backup_private_directory->Fsync();
}
if (s.ok() && private_directory_ != nullptr) {
s = private_directory_->Fsync();
}
if (s.ok() && meta_directory_ != nullptr) {
s = meta_directory_->Fsync();
}
if (s.ok() && shared_directory_ != nullptr) {
s = shared_directory_->Fsync();
}
if (s.ok() && backup_directory_ != nullptr) {
s = backup_directory_->Fsync();
}
}
if (s.ok()) {
backup_statistics_.IncrementNumberSuccessBackup();
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (!s.ok()) {
backup_statistics_.IncrementNumberFailBackup();
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// clean all the files we might have created
ROCKS_LOG_INFO(options_.info_log, "Backup failed -- %s",
s.ToString().c_str());
ROCKS_LOG_INFO(options_.info_log, "Backup Statistics %s\n",
backup_statistics_.ToString().c_str());
// delete files that we might have already written
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
might_need_garbage_collect_ = true;
DeleteBackup(new_backup_id);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return s;
}
// here we know that we succeeded and installed the new backup
// in the LATEST_BACKUP file
latest_backup_id_ = new_backup_id;
latest_valid_backup_id_ = new_backup_id;
ROCKS_LOG_INFO(options_.info_log, "Backup DONE. All is good");
// backup_speed is in byte/second
double backup_speed = new_backup->GetSize() / (1.048576 * backup_time);
ROCKS_LOG_INFO(options_.info_log, "Backup number of files: %u",
new_backup->GetNumberFiles());
char human_size[16];
AppendHumanBytes(new_backup->GetSize(), human_size, sizeof(human_size));
ROCKS_LOG_INFO(options_.info_log, "Backup size: %s", human_size);
ROCKS_LOG_INFO(options_.info_log, "Backup time: %" PRIu64 " microseconds",
backup_time);
ROCKS_LOG_INFO(options_.info_log, "Backup speed: %.3f MB/s", backup_speed);
ROCKS_LOG_INFO(options_.info_log, "Backup Statistics %s",
backup_statistics_.ToString().c_str());
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return s;
}
Status BackupEngineImpl::PurgeOldBackups(uint32_t num_backups_to_keep) {
assert(initialized_);
assert(!read_only_);
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
// Best effort deletion even with errors
Status overall_status = Status::OK();
ROCKS_LOG_INFO(options_.info_log, "Purging old backups, keeping %u",
num_backups_to_keep);
std::vector<BackupID> to_delete;
auto itr = backups_.begin();
while ((backups_.size() - to_delete.size()) > num_backups_to_keep) {
to_delete.push_back(itr->first);
itr++;
}
for (auto backup_id : to_delete) {
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
auto s = DeleteBackupInternal(backup_id);
if (!s.ok()) {
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
overall_status = s;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
// Clean up after any incomplete backup deletion, potentially from
// earlier session.
if (might_need_garbage_collect_) {
auto s = GarbageCollect();
if (!s.ok() && overall_status.ok()) {
overall_status = s;
}
}
return overall_status;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
Status BackupEngineImpl::DeleteBackup(BackupID backup_id) {
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
auto s1 = DeleteBackupInternal(backup_id);
auto s2 = Status::OK();
// Clean up after any incomplete backup deletion, potentially from
// earlier session.
if (might_need_garbage_collect_) {
s2 = GarbageCollect();
}
if (!s1.ok()) {
return s1;
} else {
return s2;
}
}
// Does not auto-GarbageCollect
Status BackupEngineImpl::DeleteBackupInternal(BackupID backup_id) {
assert(initialized_);
assert(!read_only_);
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
ROCKS_LOG_INFO(options_.info_log, "Deleting backup %u", backup_id);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
auto backup = backups_.find(backup_id);
if (backup != backups_.end()) {
auto s = backup->second->Delete();
if (!s.ok()) {
return s;
}
backups_.erase(backup);
} else {
auto corrupt = corrupt_backups_.find(backup_id);
if (corrupt == corrupt_backups_.end()) {
return Status::NotFound("Backup not found");
}
auto s = corrupt->second.second->Delete();
if (!s.ok()) {
return s;
}
corrupt_backups_.erase(corrupt);
}
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
// After removing meta file, best effort deletion even with errors.
// (Don't delete other files if we can't delete the meta file right
// now.)
std::vector<std::string> to_delete;
for (auto& itr : backuped_file_infos_) {
if (itr.second->refs == 0) {
Status s = backup_env_->DeleteFile(GetAbsolutePath(itr.first));
ROCKS_LOG_INFO(options_.info_log, "Deleting %s -- %s", itr.first.c_str(),
s.ToString().c_str());
to_delete.push_back(itr.first);
if (!s.ok()) {
// Trying again later might work
might_need_garbage_collect_ = true;
}
}
}
for (auto& td : to_delete) {
backuped_file_infos_.erase(td);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
// take care of private dirs -- GarbageCollect() will take care of them
// if they are not empty
std::string private_dir = GetPrivateFileRel(backup_id);
Status s = backup_env_->DeleteDir(GetAbsolutePath(private_dir));
ROCKS_LOG_INFO(options_.info_log, "Deleting private dir %s -- %s",
private_dir.c_str(), s.ToString().c_str());
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
if (!s.ok()) {
// Full gc or trying again later might work
might_need_garbage_collect_ = true;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return Status::OK();
}
void BackupEngineImpl::GetBackupInfo(std::vector<BackupInfo>* backup_info) {
assert(initialized_);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
backup_info->reserve(backups_.size());
for (auto& backup : backups_) {
if (!backup.second->Empty()) {
backup_info->push_back(BackupInfo(
backup.first, backup.second->GetTimestamp(), backup.second->GetSize(),
backup.second->GetNumberFiles(), backup.second->GetAppMetadata()));
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
}
}
void
BackupEngineImpl::GetCorruptedBackups(
std::vector<BackupID>* corrupt_backup_ids) {
assert(initialized_);
corrupt_backup_ids->reserve(corrupt_backups_.size());
for (auto& backup : corrupt_backups_) {
corrupt_backup_ids->push_back(backup.first);
}
}
Status BackupEngineImpl::RestoreDBFromBackup(const RestoreOptions& options,
BackupID backup_id,
const std::string& db_dir,
const std::string& wal_dir) {
assert(initialized_);
auto corrupt_itr = corrupt_backups_.find(backup_id);
if (corrupt_itr != corrupt_backups_.end()) {
return corrupt_itr->second.first;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
auto backup_itr = backups_.find(backup_id);
if (backup_itr == backups_.end()) {
return Status::NotFound("Backup not found");
}
auto& backup = backup_itr->second;
if (backup->Empty()) {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return Status::NotFound("Backup not found");
}
ROCKS_LOG_INFO(options_.info_log, "Restoring backup id %u\n", backup_id);
ROCKS_LOG_INFO(options_.info_log, "keep_log_files: %d\n",
static_cast<int>(options.keep_log_files));
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// just in case. Ignore errors
db_env_->CreateDirIfMissing(db_dir);
db_env_->CreateDirIfMissing(wal_dir);
if (options.keep_log_files) {
// delete files in db_dir, but keep all the log files
DeleteChildren(db_dir, 1 << kWalFile);
// move all the files from archive dir to wal_dir
std::string archive_dir = ArchivalDirectory(wal_dir);
std::vector<std::string> archive_files;
db_env_->GetChildren(archive_dir, &archive_files); // ignore errors
for (const auto& f : archive_files) {
uint64_t number;
FileType type;
bool ok = ParseFileName(f, &number, &type);
if (ok && type == kWalFile) {
ROCKS_LOG_INFO(options_.info_log,
"Moving log file from archive/ to wal_dir: %s",
f.c_str());
Status s =
db_env_->RenameFile(archive_dir + "/" + f, wal_dir + "/" + f);
if (!s.ok()) {
// if we can't move log file from archive_dir to wal_dir,
// we should fail, since it might mean data loss
return s;
}
}
}
} else {
DeleteChildren(wal_dir);
DeleteChildren(ArchivalDirectory(wal_dir));
DeleteChildren(db_dir);
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
RateLimiter* rate_limiter = options_.restore_rate_limiter.get();
if (rate_limiter) {
copy_file_buffer_size_ =
static_cast<size_t>(rate_limiter->GetSingleBurstBytes());
}
Status s;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::vector<RestoreAfterCopyOrCreateWorkItem> restore_items_to_finish;
for (const auto& file_info : backup->GetFiles()) {
const std::string& file = file_info->filename;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
std::string dst;
// 1. extract the filename
size_t slash = file.find_last_of('/');
// file will either be shared/<file>, shared_checksum/<file_crc32c_size>,
// shared_checksum/<file_session>, shared_checksum/<file_crc32c_session>,
// or private/<number>/<file>
assert(slash != std::string::npos);
dst = file.substr(slash + 1);
// if the file was in shared_checksum, extract the real file name
// in this case the file is <number>_<checksum>_<size>.<type>,
// <number>_<session>.<type>, or <number>_<checksum>_<session>.<type>
if (file.substr(0, slash) == GetSharedChecksumDirRel()) {
dst = GetFileFromChecksumFile(dst);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
// 2. find the filetype
uint64_t number;
FileType type;
bool ok = ParseFileName(dst, &number, &type);
if (!ok) {
return Status::Corruption("Backup corrupted: Fail to parse filename " +
dst);
}
// 3. Construct the final path
// kWalFile lives in wal_dir and all the rest live in db_dir
dst = ((type == kWalFile) ? wal_dir : db_dir) + "/" + dst;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
ROCKS_LOG_INFO(options_.info_log, "Restoring %s to %s\n", file.c_str(),
dst.c_str());
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
CopyOrCreateWorkItem copy_or_create_work_item(
GetAbsolutePath(file), dst, "" /* contents */, backup_env_, db_env_,
EnvOptions() /* src_env_options */, false, rate_limiter,
0 /* size_limit */);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
RestoreAfterCopyOrCreateWorkItem after_copy_or_create_work_item(
copy_or_create_work_item.result.get_future(), file_info->checksum_hex);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
files_to_copy_or_create_.write(std::move(copy_or_create_work_item));
restore_items_to_finish.push_back(
std::move(after_copy_or_create_work_item));
}
Status item_status;
for (auto& item : restore_items_to_finish) {
item.result.wait();
auto result = item.result.get();
item_status = result.status;
// Note: It is possible that both of the following bad-status cases occur
// during copying. But, we only return one status.
if (!item_status.ok()) {
s = item_status;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
break;
} else if (item.checksum_hex != result.checksum_hex) {
s = Status::Corruption("Checksum check failed");
break;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
ROCKS_LOG_INFO(options_.info_log, "Restoring done -- %s\n",
s.ToString().c_str());
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return s;
}
Status BackupEngineImpl::VerifyBackup(BackupID backup_id,
bool verify_with_checksum) {
// Check if backup_id is corrupted, or valid and registered
assert(initialized_);
auto corrupt_itr = corrupt_backups_.find(backup_id);
if (corrupt_itr != corrupt_backups_.end()) {
return corrupt_itr->second.first;
}
auto backup_itr = backups_.find(backup_id);
if (backup_itr == backups_.end()) {
return Status::NotFound();
}
auto& backup = backup_itr->second;
if (backup->Empty()) {
return Status::NotFound();
}
ROCKS_LOG_INFO(options_.info_log, "Verifying backup id %u\n", backup_id);
// Find all existing backup files belong to backup_id
std::unordered_map<std::string, uint64_t> curr_abs_path_to_size;
for (const auto& rel_dir : {GetPrivateFileRel(backup_id), GetSharedFileRel(),
GetSharedFileWithChecksumRel()}) {
const auto abs_dir = GetAbsolutePath(rel_dir);
InsertPathnameToSizeBytes(abs_dir, backup_env_, &curr_abs_path_to_size);
}
// For all files registered in backup
for (const auto& file_info : backup->GetFiles()) {
const auto abs_path = GetAbsolutePath(file_info->filename);
// check existence of the file
if (curr_abs_path_to_size.find(abs_path) == curr_abs_path_to_size.end()) {
return Status::NotFound("File missing: " + abs_path);
}
// verify file size
if (file_info->size != curr_abs_path_to_size[abs_path]) {
std::string size_info("Expected file size is " +
ToString(file_info->size) +
" while found file size is " +
ToString(curr_abs_path_to_size[abs_path]));
return Status::Corruption("File corrupted: File size mismatch for " +
abs_path + ": " + size_info);
}
if (verify_with_checksum) {
// verify file checksum
std::string checksum_hex;
ROCKS_LOG_INFO(options_.info_log, "Verifying %s checksum...\n",
abs_path.c_str());
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
ReadFileAndComputeChecksum(abs_path, backup_env_, EnvOptions(),
0 /* size_limit */, &checksum_hex);
if (file_info->checksum_hex != checksum_hex) {
std::string checksum_info(
"Expected checksum is " + file_info->checksum_hex +
" while computed checksum is " + checksum_hex);
return Status::Corruption("File corrupted: Checksum mismatch for " +
abs_path + ": " + checksum_info);
}
}
}
return Status::OK();
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
Status BackupEngineImpl::CopyOrCreateFile(
const std::string& src, const std::string& dst, const std::string& contents,
Env* src_env, Env* dst_env, const EnvOptions& src_env_options, bool sync,
RateLimiter* rate_limiter, uint64_t* size, std::string* checksum_hex,
uint64_t size_limit, std::function<void()> progress_callback) {
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
assert(src.empty() != contents.empty());
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
Status s;
std::unique_ptr<WritableFile> dst_file;
std::unique_ptr<SequentialFile> src_file;
EnvOptions dst_env_options;
dst_env_options.use_mmap_writes = false;
// TODO:(gzh) maybe use direct reads/writes here if possible
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (size != nullptr) {
*size = 0;
}
uint32_t checksum_value = 0;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// Check if size limit is set. if not, set it to very big number
if (size_limit == 0) {
size_limit = std::numeric_limits<uint64_t>::max();
}
s = dst_env->NewWritableFile(dst, &dst_file, dst_env_options);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
if (s.ok() && !src.empty()) {
s = src_env->NewSequentialFile(src, &src_file, src_env_options);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
if (!s.ok()) {
return s;
}
Introduce a new storage specific Env API (#5761) Summary: The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc. This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO. The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before. This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection. The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761 Differential Revision: D18868376 Pulled By: anand1976 fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 23:47:08 +01:00
std::unique_ptr<WritableFileWriter> dest_writer(new WritableFileWriter(
NewLegacyWritableFileWrapper(std::move(dst_file)), dst, dst_env_options));
std::unique_ptr<SequentialFileReader> src_reader;
std::unique_ptr<char[]> buf;
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
if (!src.empty()) {
Introduce a new storage specific Env API (#5761) Summary: The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc. This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO. The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before. This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection. The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761 Differential Revision: D18868376 Pulled By: anand1976 fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 23:47:08 +01:00
src_reader.reset(new SequentialFileReader(
NewLegacySequentialFileWrapper(src_file), src));
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
buf.reset(new char[copy_file_buffer_size_]);
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
Slice data;
uint64_t processed_buffer_size = 0;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
do {
if (stop_backup_.load(std::memory_order_acquire)) {
return Status::Incomplete("Backup stopped");
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
if (!src.empty()) {
size_t buffer_to_read = (copy_file_buffer_size_ < size_limit)
? copy_file_buffer_size_
: static_cast<size_t>(size_limit);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
s = src_reader->Read(buffer_to_read, &data, buf.get());
processed_buffer_size += buffer_to_read;
} else {
data = contents;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
size_limit -= data.size();
TEST_SYNC_POINT_CALLBACK(
"BackupEngineImpl::CopyOrCreateFile:CorruptionDuringBackup",
(src.length() > 4 && src.rfind(".sst") == src.length() - 4) ? &data
: nullptr);
if (!s.ok()) {
return s;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (size != nullptr) {
*size += data.size();
}
if (checksum_hex != nullptr) {
checksum_value = crc32c::Extend(checksum_value, data.data(), data.size());
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
s = dest_writer->Append(data);
if (rate_limiter != nullptr) {
rate_limiter->Request(data.size(), Env::IO_LOW, nullptr /* stats */,
RateLimiter::OpType::kWrite);
}
if (processed_buffer_size > options_.callback_trigger_interval_size) {
processed_buffer_size -= options_.callback_trigger_interval_size;
std::lock_guard<std::mutex> lock(byte_report_mutex_);
progress_callback();
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
} while (s.ok() && contents.empty() && data.size() > 0 && size_limit > 0);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// Convert uint32_t checksum to hex checksum
if (checksum_hex != nullptr) {
checksum_hex->assign(ChecksumInt32ToHex(checksum_value));
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (s.ok() && sync) {
s = dest_writer->Sync(false);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
if (s.ok()) {
s = dest_writer->Close();
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return s;
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
// fname will always start with "/"
Status BackupEngineImpl::AddBackupFileWorkItem(
std::unordered_set<std::string>& live_dst_paths,
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::vector<BackupAfterCopyOrCreateWorkItem>& backup_items_to_finish,
BackupID backup_id, bool shared, const std::string& src_dir,
const std::string& fname, const EnvOptions& src_env_options,
RateLimiter* rate_limiter, uint64_t size_bytes, uint64_t size_limit,
bool shared_checksum, std::function<void()> progress_callback,
const std::string& contents, const std::string& src_checksum_func_name,
const std::string& src_checksum_str) {
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
assert(!fname.empty() && fname[0] == '/');
assert(contents.empty() != src_dir.empty());
std::string dst_relative = fname.substr(1);
std::string dst_relative_tmp;
Status s;
std::string checksum_hex;
std::string db_id;
std::string db_session_id;
// whether the checksum for a table file is available
bool has_checksum = false;
// Whenever a default checksum function name is passed in, we will compares
// the corresponding checksum values after copying. Note that only table files
// may have a known checksum function name passed in.
//
// If no default checksum function name is passed in and db session id is not
// available, we will calculate the checksum *before* copying in two cases
// (we always calcuate checksums when copying or creating for any file types):
// a) share_files_with_checksum is true and file type is table;
// b) share_table_files is true and the file exists already.
//
// Step 0: Check if default checksum function name is passed in
if (kDbFileChecksumFuncName == src_checksum_func_name) {
if (src_checksum_str == kUnknownFileChecksum) {
return Status::Aborted("Unknown checksum value for " + fname);
}
checksum_hex = ChecksumStrToHex(src_checksum_str);
has_checksum = true;
}
// Step 1: Prepare the relative path to destination
if (shared && shared_checksum) {
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
if (GetNamingNoFlags() != BackupableDBOptions::kLegacyCrc32cAndFileSize) {
// Prepare db_session_id to add to the file name
// Ignore the returned status
// In the failed cases, db_id and db_session_id will be empty
GetFileDbIdentities(db_env_, src_env_options, src_dir + fname, &db_id,
&db_session_id);
}
// Calculate checksum if checksum and db session id are not available.
// If db session id is available, we will not calculate the checksum
// since the session id should suffice to avoid file name collision in
// the shared_checksum directory.
if (!has_checksum && db_session_id.empty()) {
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
s = ReadFileAndComputeChecksum(src_dir + fname, db_env_, src_env_options,
size_limit, &checksum_hex);
if (!s.ok()) {
return s;
}
has_checksum = true;
}
if (size_bytes == port::kMaxUint64) {
return Status::NotFound("File missing: " + src_dir + fname);
}
// dst_relative depends on the following conditions:
Restore file size in backup table file names (and other cleanup) (#7400) Summary: Prior to 6.12, backup files using share_files_with_checksum had the file size encoded in the file name, after the last '\_' and before the last '.'. We considered this an implementation detail subject to change, and indeed removed this information from the file name (with an option to use old behavior) because it was considered ineffective/inefficient for file name uniqueness. However, some downstream RocksDB users were relying on this information since the file size is not explicitly in the backup manifest file. This primary purpose of this change is "retrofitting" the 6.12 release (not yet a public release) to simultaneously support the benefits of the new naming scheme (I/O performance and data correctness at scale) and preserve the file size information, both as default behaviors. With this change, we are essentially making the file size information encoded in the file name an official, though obscure, extension of the backup meta file format. We preserve an option (kLegacyCrc32cAndFileSize) to use the original "legacy" naming scheme, with its caveats, and make it easy to omit the file size information (no kFlagIncludeFileSize), for more compact file names. But note that changing the naming scheme used on an existing db and backup directory can lead to transient space amplification, as some files will be stored under two names in the shared_checksum directory. Because some backups were saved using the original 6.12 naming scheme, we offer two ways of dealing with those files: SST files generated by older 6.12 versions can either use the default naming scheme in effect when the SST files were generated (kFlagMatchInterimNaming, default, no transient space amplification) or can use a new naming scheme (no kFlagMatchInterimNaming, potential space amplification because some already stored files getting a new name). We don't have a natural way to detect which files were generated by previous 6.12 versions, but this change hacks one in by changing DB session ids to now use a more concise encoding, reducing file name length, saving ~dozen bytes from SST files, and making them visually distinct from DB ids so that they are less likely to be mixed up. Two final auxiliary notes: Recognizing that the backup file names have become a de facto part of the backup meta schema, this change makes them easier to parse and extend by putting a distinct marker, 's', before DB session ids embedded in the name. When we extend this to allow custom checksums in the name, they can get their own marker to ensure safe parsing. For backward compatibility, file size does not get a marker but is assumed for `_[0-9]+[.]` Another change from initial 6.12 default behavior is never including file custom checksum in the file name. Looking ahead to 6.13, we do not want the default behavior to cause backup space amplification for someone turning on file custom checksum checking in BackupEngine; we want that to be an easy decision. When implemented, including file custom checksums in backup file names will be a non-default option. Actual file name patterns and priorities, as regexes: kLegacyCrc32cAndFileSize OR pre-6.12 SST file -> [0-9]+_[0-9]+_[0-9]+[.]sst kFlagMatchInterimNaming set (default) AND early 6.12 SST file -> [0-9]+_[0-9a-fA-F-]+[.]sst kUseDbSessionId AND NOT kFlagIncludeFileSize -> [0-9]+_s[0-9A-Z]{20}[.]sst kUseDbSessionId AND kFlagIncludeFileSize (default) -> [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst We might add opt-in options for more '\_' separated data in the name, but embedded file size, if present, will always be after last '\_' and before '.sst'. This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390) Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400 Test Plan: unit tests included. Sync point callbacks are used to mimic previous version SST files. Reviewed By: ajkr Differential Revision: D23759587 Pulled By: pdillinger fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 19:22:56 +02:00
// 1) the naming scheme is kUseDbSessionId,
// 2) db_session_id is not empty,
// 3) checksum is available in the DB manifest.
// If 1,2,3) are satisfied, then dst_relative will be of the form:
// shared_checksum/<file_number>_<checksum>_<db_session_id>.sst
// If 1,2) are satisfied, then dst_relative will be of the form:
// shared_checksum/<file_number>_<db_session_id>.sst
// Otherwise, dst_relative is of the form
// shared_checksum/<file_number>_<checksum>_<size>.sst
dst_relative = GetSharedFileWithChecksum(
dst_relative, has_checksum, checksum_hex, size_bytes, db_session_id);
dst_relative_tmp = GetSharedFileWithChecksumRel(dst_relative, true);
dst_relative = GetSharedFileWithChecksumRel(dst_relative, false);
} else if (shared) {
dst_relative_tmp = GetSharedFileRel(dst_relative, true);
dst_relative = GetSharedFileRel(dst_relative, false);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
} else {
dst_relative = GetPrivateFileRel(backup_id, false, dst_relative);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
// We copy into `temp_dest_path` and, once finished, rename it to
// `final_dest_path`. This allows files to atomically appear at
// `final_dest_path`. We can copy directly to the final path when atomicity
// is unnecessary, like for files in private backup directories.
const std::string* copy_dest_path;
std::string temp_dest_path;
std::string final_dest_path = GetAbsolutePath(dst_relative);
if (!dst_relative_tmp.empty()) {
temp_dest_path = GetAbsolutePath(dst_relative_tmp);
copy_dest_path = &temp_dest_path;
} else {
copy_dest_path = &final_dest_path;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// Step 2: Determine whether to copy or not
// if it's shared, we also need to check if it exists -- if it does, no need
// to copy it again.
bool need_to_copy = true;
// true if final_dest_path is the same path as another live file
const bool same_path =
live_dst_paths.find(final_dest_path) != live_dst_paths.end();
bool file_exists = false;
if (shared && !same_path) {
// Should be in shared directory but not a live path, check existence in
// shared directory
Status exist = backup_env_->FileExists(final_dest_path);
if (exist.ok()) {
file_exists = true;
} else if (exist.IsNotFound()) {
file_exists = false;
} else {
assert(s.IsIOError());
return exist;
}
}
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
if (!contents.empty()) {
need_to_copy = false;
} else if (shared && (same_path || file_exists)) {
need_to_copy = false;
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
auto find_result = backuped_file_infos_.find(dst_relative);
if (find_result == backuped_file_infos_.end() && !same_path) {
// file exists but not referenced
ROCKS_LOG_INFO(
options_.info_log,
"%s already present, but not referenced by any backup. We will "
"overwrite the file.",
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
fname.c_str());
need_to_copy = true;
backup_env_->DeleteFile(final_dest_path);
} else {
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
// file exists and referenced
if (!has_checksum) {
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
if (!same_path) {
assert(find_result != backuped_file_infos_.end());
// Note: to save I/O on incremental backups, we copy prior known
// checksum of the file instead of reading entire file contents
// to recompute it.
checksum_hex = find_result->second->checksum_hex;
has_checksum = true;
// Regarding corruption detection, consider:
// (a) the DB file is corrupt (since previous backup) and the backup
// file is OK: we failed to detect, but the backup is safe. DB can
// be repaired/restored once its corruption is detected.
// (b) the backup file is corrupt (since previous backup) and the
// db file is OK: we failed to detect, but the backup is corrupt.
// CreateNewBackup should support fast incremental backups and
// there's no way to support that without reading all the files.
// We might add an option for extra checks on incremental backup,
// but until then, use VerifyBackups to check existing backup data.
// (c) file name collision with legitimately different content.
// This is almost inconceivable with a well-generated DB session
// ID, but even in that case, we double check the file sizes in
// BackupMeta::AddFile.
} else {
// same_path should not happen for a standard DB, so OK to
// read file contents to check for checksum mismatch between
// two files from same DB getting same name.
s = ReadFileAndComputeChecksum(src_dir + fname, db_env_,
src_env_options, size_limit,
&checksum_hex);
if (!s.ok()) {
return s;
}
}
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
}
if (!db_session_id.empty()) {
ROCKS_LOG_INFO(options_.info_log,
"%s already present, with checksum %s, size %" PRIu64
" and DB session identity %s",
fname.c_str(), checksum_hex.c_str(), size_bytes,
db_session_id.c_str());
} else {
ROCKS_LOG_INFO(options_.info_log,
"%s already present, with checksum %s and size %" PRIu64,
fname.c_str(), checksum_hex.c_str(), size_bytes);
}
}
}
live_dst_paths.insert(final_dest_path);
// Step 3: Add work item
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
if (!contents.empty() || need_to_copy) {
ROCKS_LOG_INFO(options_.info_log, "Copying %s to %s", fname.c_str(),
copy_dest_path->c_str());
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
CopyOrCreateWorkItem copy_or_create_work_item(
src_dir.empty() ? "" : src_dir + fname, *copy_dest_path, contents,
db_env_, backup_env_, src_env_options, options_.sync, rate_limiter,
size_limit, progress_callback, has_checksum, src_checksum_func_name,
checksum_hex, db_id, db_session_id);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
BackupAfterCopyOrCreateWorkItem after_copy_or_create_work_item(
copy_or_create_work_item.result.get_future(), shared, need_to_copy,
backup_env_, temp_dest_path, final_dest_path, dst_relative);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
files_to_copy_or_create_.write(std::move(copy_or_create_work_item));
backup_items_to_finish.push_back(std::move(after_copy_or_create_work_item));
} else {
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
std::promise<CopyOrCreateResult> promise_result;
BackupAfterCopyOrCreateWorkItem after_copy_or_create_work_item(
promise_result.get_future(), shared, need_to_copy, backup_env_,
temp_dest_path, final_dest_path, dst_relative);
Handle concurrent manifest update and backup creation Summary: Fixed two related race conditions in backup creation. (1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files from being deleted while it is copying; however, the MANIFEST file could still rotate during this time. The fix is to stop deleting the old manifest in the rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs (can only happen when file deletions are enabled). (2) CreateNewBackup() did not account for the CURRENT file being mutable. This is significant because the files returned by GetLiveFiles() contain a particular manifest filename, but the manifest to which CURRENT refers can change at any time. This causes problems when CURRENT changes between the call to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I manually forge a CURRENT file referring to the manifest filename returned in GetLiveFiles(). (2) also applies to the checkpointing code, so let me know if this approach is good and I'll make the same change there. Test Plan: new test for roll manifest during backup creation. running the test before this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory running the test after this change: $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation ... [ RUN ] BackupableDBTest.ChangeManifestDuringBackupCreation [ OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms) Reviewers: IslamAbdelRahman, anthony, sdong Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 21:56:55 +01:00
backup_items_to_finish.push_back(std::move(after_copy_or_create_work_item));
CopyOrCreateResult result;
result.status = s;
result.size = size_bytes;
result.checksum_hex = std::move(checksum_hex);
result.db_id = std::move(db_id);
result.db_session_id = std::move(db_session_id);
promise_result.set_value(std::move(result));
}
return s;
}
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
Status BackupEngineImpl::ReadFileAndComputeChecksum(
const std::string& src, Env* src_env, const EnvOptions& src_env_options,
uint64_t size_limit, std::string* checksum_hex) {
if (checksum_hex == nullptr) {
return Status::Aborted("Checksum pointer is null");
}
uint32_t checksum_value = 0;
if (size_limit == 0) {
size_limit = std::numeric_limits<uint64_t>::max();
}
std::unique_ptr<SequentialFile> src_file;
Status s = src_env->NewSequentialFile(src, &src_file, src_env_options);
if (!s.ok()) {
return s;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
std::unique_ptr<SequentialFileReader> src_reader(
Introduce a new storage specific Env API (#5761) Summary: The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc. This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO. The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before. This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection. The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761 Differential Revision: D18868376 Pulled By: anand1976 fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 23:47:08 +01:00
new SequentialFileReader(NewLegacySequentialFileWrapper(src_file), src));
std::unique_ptr<char[]> buf(new char[copy_file_buffer_size_]);
Slice data;
do {
if (stop_backup_.load(std::memory_order_acquire)) {
return Status::Incomplete("Backup stopped");
}
size_t buffer_to_read = (copy_file_buffer_size_ < size_limit) ?
copy_file_buffer_size_ : static_cast<size_t>(size_limit);
s = src_reader->Read(buffer_to_read, &data, buf.get());
if (!s.ok()) {
return s;
}
size_limit -= data.size();
checksum_value = crc32c::Extend(checksum_value, data.data(), data.size());
} while (data.size() > 0 && size_limit > 0);
checksum_hex->assign(ChecksumInt32ToHex(checksum_value));
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
return s;
}
Status BackupEngineImpl::GetFileDbIdentities(Env* src_env,
const EnvOptions& src_env_options,
const std::string& file_path,
std::string* db_id,
std::string* db_session_id) {
assert(db_id != nullptr || db_session_id != nullptr);
Options options;
options.env = src_env;
SstFileDumper sst_reader(options, file_path,
2 * 1024 * 1024
/* readahead_size */,
false /* verify_checksum */, false /* output_hex */,
false /* decode_blob_index */, src_env_options,
true /* silent */);
const TableProperties* table_properties = nullptr;
std::shared_ptr<const TableProperties> tp;
Status s = sst_reader.getStatus();
if (s.ok()) {
// Try to get table properties from the table reader of sst_reader
if (!sst_reader.ReadTableProperties(&tp).ok()) {
// Try to use table properites from the initialization of sst_reader
table_properties = sst_reader.GetInitTableProperties();
} else {
table_properties = tp.get();
}
} else {
ROCKS_LOG_INFO(options_.info_log, "Failed to read %s: %s",
file_path.c_str(), s.ToString().c_str());
return s;
}
if (table_properties != nullptr) {
if (db_id != nullptr) {
db_id->assign(table_properties->db_id);
}
if (db_session_id != nullptr) {
db_session_id->assign(table_properties->db_session_id);
if (db_session_id->empty()) {
s = Status::NotFound("DB session identity not found in " + file_path);
ROCKS_LOG_INFO(options_.info_log, "%s", s.ToString().c_str());
return s;
}
}
return Status::OK();
} else {
s = Status::Corruption("Table properties missing in " + file_path);
ROCKS_LOG_INFO(options_.info_log, "%s", s.ToString().c_str());
return s;
}
}
void BackupEngineImpl::DeleteChildren(const std::string& dir,
uint32_t file_type_filter) {
std::vector<std::string> children;
db_env_->GetChildren(dir, &children); // ignore errors
for (const auto& f : children) {
uint64_t number;
FileType type;
bool ok = ParseFileName(f, &number, &type);
if (ok && (file_type_filter & (1 << type))) {
// don't delete this file
continue;
}
db_env_->DeleteFile(dir + "/" + f); // ignore errors
}
}
Status BackupEngineImpl::InsertPathnameToSizeBytes(
const std::string& dir, Env* env,
std::unordered_map<std::string, uint64_t>* result) {
assert(result != nullptr);
std::vector<Env::FileAttributes> files_attrs;
Status status = env->FileExists(dir);
if (status.ok()) {
status = env->GetChildrenFileAttributes(dir, &files_attrs);
} else if (status.IsNotFound()) {
// Insert no entries can be considered success
status = Status::OK();
}
const bool slash_needed = dir.empty() || dir.back() != '/';
for (const auto& file_attrs : files_attrs) {
result->emplace(dir + (slash_needed ? "/" : "") + file_attrs.name,
file_attrs.size_bytes);
}
return status;
}
Status BackupEngineImpl::GarbageCollect() {
assert(!read_only_);
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
// We will make a best effort to remove all garbage even in the presence
// of inconsistencies or I/O failures that inhibit finding garbage.
Status overall_status = Status::OK();
// If all goes well, we don't need another auto-GC this session
might_need_garbage_collect_ = false;
ROCKS_LOG_INFO(options_.info_log, "Starting garbage collection");
// delete obsolete shared files
for (bool with_checksum : {false, true}) {
std::vector<std::string> shared_children;
{
std::string shared_path;
if (with_checksum) {
shared_path = GetAbsolutePath(GetSharedFileWithChecksumRel());
} else {
shared_path = GetAbsolutePath(GetSharedFileRel());
}
auto s = backup_env_->FileExists(shared_path);
if (s.ok()) {
s = backup_env_->GetChildren(shared_path, &shared_children);
} else if (s.IsNotFound()) {
s = Status::OK();
}
if (!s.ok()) {
overall_status = s;
// Trying again later might work
might_need_garbage_collect_ = true;
}
}
for (auto& child : shared_children) {
if (child == "." || child == "..") {
continue;
}
std::string rel_fname;
if (with_checksum) {
rel_fname = GetSharedFileWithChecksumRel(child);
} else {
rel_fname = GetSharedFileRel(child);
}
auto child_itr = backuped_file_infos_.find(rel_fname);
// if it's not refcounted, delete it
if (child_itr == backuped_file_infos_.end() ||
child_itr->second->refs == 0) {
// this might be a directory, but DeleteFile will just fail in that
// case, so we're good
Status s = backup_env_->DeleteFile(GetAbsolutePath(rel_fname));
ROCKS_LOG_INFO(options_.info_log, "Deleting %s -- %s",
rel_fname.c_str(), s.ToString().c_str());
backuped_file_infos_.erase(rel_fname);
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
if (!s.ok()) {
// Trying again later might work
might_need_garbage_collect_ = true;
}
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// delete obsolete private files
std::vector<std::string> private_children;
{
auto s = backup_env_->GetChildren(GetAbsolutePath(GetPrivateDirRel()),
&private_children);
if (!s.ok()) {
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
overall_status = s;
// Trying again later might work
might_need_garbage_collect_ = true;
}
}
for (auto& child : private_children) {
More fixes to auto-GarbageCollect in BackupEngine (#6023) Summary: Production: * Fixes GarbageCollect (and auto-GC triggered by PurgeOldBackups, DeleteBackup, or CreateNewBackup) to clean up backup directory independent of current settings (except max_valid_backups_to_open; see issue https://github.com/facebook/rocksdb/issues/4997) and prior settings used with same backup directory. * Fixes GarbageCollect (and auto-GC) not to attempt to remove "." and ".." entries from directories. * Clarifies contract with users in modifying BackupEngine operations. In short, leftovers from any incomplete operation are cleaned up by any subsequent call to that same kind of operation (PurgeOldBackups and DeleteBackup considered the same kind of operation). GarbageCollect is available to clean up after all kinds. (NB: right now PurgeOldBackups and DeleteBackup will clean up after incomplete CreateNewBackup, but we aren't promising to continue that behavior.) Pull Request resolved: https://github.com/facebook/rocksdb/pull/6023 Test Plan: * Refactors open parameters to use an option enum, for readability, etc. (Also fixes an unused parameter bug in the redundant OpenDBAndBackupEngineShareWithChecksum.) * Fixes an apparent bug in ShareTableFilesWithChecksumsTransition in which old backup data was destroyed in the transition to be tested. That test is now augmented to ensure GarbageCollect (or auto-GC) does not remove shared files when BackupEngine is opened with share_table_files=false. * Augments DeleteTmpFiles test to ensure that CreateNewBackup does auto-GC when an incompletely created backup is detected. Differential Revision: D18453559 Pulled By: pdillinger fbshipit-source-id: 5e54e7b08d711b161bc9c656181012b69a8feac4
2019-11-14 15:18:23 +01:00
if (child == "." || child == "..") {
continue;
}
BackupID backup_id = 0;
bool tmp_dir = child.find(".tmp") != std::string::npos;
sscanf(child.c_str(), "%u", &backup_id);
if (!tmp_dir && // if it's tmp_dir, delete it
(backup_id == 0 || backups_.find(backup_id) != backups_.end())) {
// it's either not a number or it's still alive. continue
continue;
}
// here we have to delete the dir and all its children
std::string full_private_path =
GetAbsolutePath(GetPrivateFileRel(backup_id));
std::vector<std::string> subchildren;
backup_env_->GetChildren(full_private_path, &subchildren);
for (auto& subchild : subchildren) {
More fixes to auto-GarbageCollect in BackupEngine (#6023) Summary: Production: * Fixes GarbageCollect (and auto-GC triggered by PurgeOldBackups, DeleteBackup, or CreateNewBackup) to clean up backup directory independent of current settings (except max_valid_backups_to_open; see issue https://github.com/facebook/rocksdb/issues/4997) and prior settings used with same backup directory. * Fixes GarbageCollect (and auto-GC) not to attempt to remove "." and ".." entries from directories. * Clarifies contract with users in modifying BackupEngine operations. In short, leftovers from any incomplete operation are cleaned up by any subsequent call to that same kind of operation (PurgeOldBackups and DeleteBackup considered the same kind of operation). GarbageCollect is available to clean up after all kinds. (NB: right now PurgeOldBackups and DeleteBackup will clean up after incomplete CreateNewBackup, but we aren't promising to continue that behavior.) Pull Request resolved: https://github.com/facebook/rocksdb/pull/6023 Test Plan: * Refactors open parameters to use an option enum, for readability, etc. (Also fixes an unused parameter bug in the redundant OpenDBAndBackupEngineShareWithChecksum.) * Fixes an apparent bug in ShareTableFilesWithChecksumsTransition in which old backup data was destroyed in the transition to be tested. That test is now augmented to ensure GarbageCollect (or auto-GC) does not remove shared files when BackupEngine is opened with share_table_files=false. * Augments DeleteTmpFiles test to ensure that CreateNewBackup does auto-GC when an incompletely created backup is detected. Differential Revision: D18453559 Pulled By: pdillinger fbshipit-source-id: 5e54e7b08d711b161bc9c656181012b69a8feac4
2019-11-14 15:18:23 +01:00
if (subchild == "." || subchild == "..") {
continue;
}
Status s = backup_env_->DeleteFile(full_private_path + subchild);
ROCKS_LOG_INFO(options_.info_log, "Deleting %s -- %s",
(full_private_path + subchild).c_str(),
s.ToString().c_str());
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
if (!s.ok()) {
// Trying again later might work
might_need_garbage_collect_ = true;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
// finally delete the private dir
Status s = backup_env_->DeleteDir(full_private_path);
ROCKS_LOG_INFO(options_.info_log, "Deleting dir %s -- %s",
full_private_path.c_str(), s.ToString().c_str());
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
if (!s.ok()) {
// Trying again later might work
might_need_garbage_collect_ = true;
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
Auto-GarbageCollect on PurgeOldBackups and DeleteBackup (#6015) Summary: Only if there is a crash, power failure, or I/O error in DeleteBackup, shared or private files from the backup might be left behind that are not cleaned up by PurgeOldBackups or DeleteBackup-- only by GarbageCollect. This makes the BackupEngine API "leaky by default." Even if it means a modest performance hit, I think we should make Delete and Purge do as they say, with ongoing best effort: i.e. future calls will attempt to finish any incomplete work from earlier calls. This change does that by having DeleteBackup and PurgeOldBackups do a GarbageCollect, unless (to minimize performance hit) this BackupEngine has already done a GarbageCollect and there have been no deletion-related I/O errors in that GarbageCollect or since then. Rejected alternative 1: remove meta file last instead of first. This would in theory turn partially deleted backups into corrupted backups, but code changes would be needed to allow the missing files and consider it acceptably corrupt, rather than failing to open the BackupEngine. This might be a reasonable choice, but I mostly rejected it because it doesn't solve the legacy problem of cleaning up existing lingering files. Rejected alternative 2: use a deletion marker file. If deletion started with creating a file that marks a backup as flagged for deletion, then we could reliably detect partially deleted backups and efficiently finish removing them. In addition to not solving the legacy problem, this could be precarious if there's a disk full situation, and we try to create a new file in order to delete some files. Ugh. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6015 Test Plan: Updated unit tests Differential Revision: D18401333 Pulled By: pdillinger fbshipit-source-id: 12944e372ce6809f3f5a4c416c3b321a8927d925
2019-11-09 04:13:41 +01:00
assert(overall_status.ok() || might_need_garbage_collect_);
return overall_status;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
// ------- BackupMeta class --------
Status BackupEngineImpl::BackupMeta::AddFile(
std::shared_ptr<FileInfo> file_info) {
auto itr = file_infos_->find(file_info->filename);
if (itr == file_infos_->end()) {
auto ret = file_infos_->insert({file_info->filename, file_info});
if (ret.second) {
itr = ret.first;
itr->second->refs = 1;
} else {
// if this happens, something is seriously wrong
return Status::Corruption("In memory metadata insertion error");
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
} else {
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
// Compare sizes, because we scanned that off the filesystem on both
// ends. This is like a check in VerifyBackup.
if (itr->second->size != file_info->size) {
std::string msg = "Size mismatch for existing backup file: ";
msg.append(file_info->filename);
msg.append(" Size in backup is " + ToString(itr->second->size) +
" while size in DB is " + ToString(file_info->size));
msg.append(
" If this DB file checks as not corrupt, try deleting old"
" backups or backing up to a different backup directory.");
return Status::Corruption(msg);
}
// Note: to save I/O, this check will pass trivially on already backed
// up files that don't have the checksum in their name. And it should
// never fail for files that do have checksum in their name.
if (itr->second->checksum_hex != file_info->checksum_hex) {
Less I/O for incremental backups, slightly better corruption detection (#7413) Summary: Two relatively simple functional changes to incremental backup behavior, integrated with a minor refactoring to reduce code redundancy and improve error/log message. There are nuances to the impact of these changes, but I believe they are fundamentally good and generally safe. Those functional changes: * Incremental backups no longer read DB table files that are already saved to a shared part of the backup directory, unless `share_files_with_checksum` is used with `kLegacyCrc32cAndFileSize` naming (discouraged) where crc32c full file checksums are needed to determine file naming. * Justification: incremental backups should not need to read the whole DB, especially without rate limiting. (Although other BackupEngine reads are not rate limited either, other non-trivial reads are generally limited by a corresponding write, as in copying files.) Also, the fact that this is not already fixed was arguably a bug/oversight in the implementation of https://github.com/facebook/rocksdb/issues/7110. * When considering whether a table file is already backed up in a shared part of backup directory, BackupEngine would already query the sizes of source (DB) and pre-existing destination (backup) files. BackupEngine now uses these file sizes to detect corruption, as at least one of (a) old backup, (b) backup in progress, or (c) current DB is corrupt if there's a size mismatch. * Justification: a random related fix that also helps to cover a small hole in corruption checking uncovered by the other functional change: * For `share_table_files` without "checksum" (not recommended), the other change regresses in detecting fundamentally unsafe use of this option combination: when you might generate different versions of same SST file number. As demonstrated by `BackupableDBTest.FailOverwritingBackups,` this regression is greatly mitigated by the new file size checking. Nevertheless, almost no reason to use `share_files_with_checksum=false` should remain, and comments are updated appropriately. Also, this change renames internal function `CalculateChecksum` to `ReadFileAndComputeChecksum` to make the performance impact of this function clear in code reviews. It is not clear what 'same_path' is for in backupable_db.cc, and I suspect it cannot be true for a DB with unique file names (like DBImpl). Nevertheless, I've tried to keep its functionality intact when `true` to minimize risk for now, despite having no unit tests for which it is true. Select impact details (much more in unit tests): For `share_files_with_checksum`, I am confident there is no regression (vs. pre-6.12) in detecting DB or backup corruption at backup creation time, mostly because the old design did not leverage this extra checksum computation for detecting inconsistencies at backup creation time. (With computed checksums in names, a recently corrupted file just looked like a different file vs. what was already backed up.) Even in the hypothetical case of DB session id collision (~100 bits entropy collision), file size in name and/or our file size check add an extra layer of protection against false success in creating an accurate new backup. (Unit test included.) `DB::VerifyChecksum` and `BackupEngine::VerifyBackup` with checksum checking are still able to catch corruptions that `CreateNewBackup` does not. Note that when custom file checksum support is added to BackupEngine, that will essentially give the same power as `DB::VerifyChecksum` into `CreateNewBackup`. We could add options for `CreateNewBackup` to cover some of what would be caught by `VerifyBackup` with checksum checking. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7413 Test Plan: Two new unit tests included, both of which fail without these changes. Although we don't test the I/O improvement directly, we test it indirectly in DB corruption detection power that was inadvertently unlocked with new backup file naming PLUS computing current content checksums (now removed). (I don't think that case of DB corruption detection justifies reading the whole DB on incremental backup.) Reviewed By: zhichao-cao Differential Revision: D23818480 Pulled By: pdillinger fbshipit-source-id: 148aff16f001af5b9fd4b22f155311c2461f1bac
2020-09-22 01:18:11 +02:00
// Should never reach here, but produce an appropriate corruption
// message in case we do in a release build.
assert(false);
std::string msg = "Checksum mismatch for existing backup file: ";
msg.append(file_info->filename);
msg.append(" Expected checksum is " + itr->second->checksum_hex +
" while computed checksum is " + file_info->checksum_hex);
msg.append(
" If this DB file checks as not corrupt, try deleting old"
" backups or backing up to a different backup directory.");
return Status::Corruption(msg);
}
++itr->second->refs; // increase refcount if already present
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
size_ += file_info->size;
files_.push_back(itr->second);
return Status::OK();
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
Status BackupEngineImpl::BackupMeta::Delete(bool delete_meta) {
Status s;
for (const auto& file : files_) {
--file->refs; // decrease refcount
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
files_.clear();
// delete meta file
if (delete_meta) {
s = env_->FileExists(meta_filename_);
if (s.ok()) {
s = env_->DeleteFile(meta_filename_);
} else if (s.IsNotFound()) {
s = Status::OK(); // nothing to delete
}
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
timestamp_ = 0;
return s;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
Slice kMetaDataPrefix("metadata ");
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// each backup meta file is of the format:
// <timestamp>
// <seq number>
// <metadata(literal string)> <metadata> (optional)
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// <number of files>
// <file1> <crc32(literal string)> <crc32c_value>
// <file2> <crc32(literal string)> <crc32c_value>
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
// ...
Status BackupEngineImpl::BackupMeta::LoadFromFile(
const std::string& backup_dir,
const std::unordered_map<std::string, uint64_t>& abs_path_to_size) {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
assert(Empty());
Status s;
std::unique_ptr<SequentialFile> backup_meta_file;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
s = env_->NewSequentialFile(meta_filename_, &backup_meta_file, EnvOptions());
if (!s.ok()) {
return s;
}
std::unique_ptr<SequentialFileReader> backup_meta_reader(
Introduce a new storage specific Env API (#5761) Summary: The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc. This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO. The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before. This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection. The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761 Differential Revision: D18868376 Pulled By: anand1976 fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 23:47:08 +01:00
new SequentialFileReader(NewLegacySequentialFileWrapper(backup_meta_file),
meta_filename_));
std::unique_ptr<char[]> buf(new char[max_backup_meta_file_size_ + 1]);
Slice data;
s = backup_meta_reader->Read(max_backup_meta_file_size_, &data, buf.get());
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (!s.ok() || data.size() == max_backup_meta_file_size_) {
return s.ok() ? Status::Corruption("File size too big") : s;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
buf[data.size()] = 0;
uint32_t num_files = 0;
char *next;
timestamp_ = strtoull(data.data(), &next, 10);
data.remove_prefix(next - data.data() + 1); // +1 for '\n'
sequence_number_ = strtoull(data.data(), &next, 10);
data.remove_prefix(next - data.data() + 1); // +1 for '\n'
if (data.starts_with(kMetaDataPrefix)) {
// app metadata present
data.remove_prefix(kMetaDataPrefix.size());
Slice hex_encoded_metadata = GetSliceUntil(&data, '\n');
bool decode_success = hex_encoded_metadata.DecodeHex(&app_metadata_);
if (!decode_success) {
return Status::Corruption(
"Failed to decode stored hex encoded app metadata");
}
}
num_files = static_cast<uint32_t>(strtoul(data.data(), &next, 10));
data.remove_prefix(next - data.data() + 1); // +1 for '\n'
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
std::vector<std::shared_ptr<FileInfo>> files;
// WART: The checksums are crc32c, not original crc32
Slice checksum_prefix("crc32 ");
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
for (uint32_t i = 0; s.ok() && i < num_files; ++i) {
auto line = GetSliceUntil(&data, '\n');
// filename is relative, i.e., shared/number.sst,
// shared_checksum/number.sst, or private/backup_id/number.sst
std::string filename = GetSliceUntil(&line, ' ').ToString();
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
uint64_t size;
const std::shared_ptr<FileInfo> file_info = GetFile(filename);
if (file_info) {
size = file_info->size;
} else {
std::string abs_path = backup_dir + "/" + filename;
try {
size = abs_path_to_size.at(abs_path);
2016-03-04 00:08:24 +01:00
} catch (std::out_of_range&) {
return Status::Corruption("Size missing for pathname: " + abs_path);
}
}
if (line.empty()) {
return Status::Corruption("File checksum is missing for " + filename +
" in " + meta_filename_);
}
uint32_t checksum_value = 0;
if (line.starts_with(checksum_prefix)) {
line.remove_prefix(checksum_prefix.size());
checksum_value = static_cast<uint32_t>(strtoul(line.data(), nullptr, 10));
if (line != ROCKSDB_NAMESPACE::ToString(checksum_value)) {
return Status::Corruption("Invalid checksum value for " + filename +
" in " + meta_filename_);
}
} else {
return Status::Corruption("Unknown checksum type for " + filename +
" in " + meta_filename_);
}
files.emplace_back(
new FileInfo(filename, size, ChecksumInt32ToHex(checksum_value)));
}
if (s.ok() && data.size() > 0) {
// file has to be read completely. if not, we count it as corruption
s = Status::Corruption("Tailing data in backup meta file in " +
meta_filename_);
}
if (s.ok()) {
files_.reserve(files.size());
for (const auto& file_info : files) {
s = AddFile(file_info);
if (!s.ok()) {
break;
}
}
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
return s;
}
Status BackupEngineImpl::BackupMeta::StoreToFile(bool sync) {
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
Status s;
std::unique_ptr<WritableFile> backup_meta_file;
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
EnvOptions env_options;
env_options.use_mmap_writes = false;
env_options.use_direct_writes = false;
s = env_->NewWritableFile(meta_tmp_filename_, &backup_meta_file, env_options);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (!s.ok()) {
return s;
}
std::ostringstream buf;
buf << timestamp_ << "\n";
buf << sequence_number_ << "\n";
if (!app_metadata_.empty()) {
std::string hex_encoded_metadata =
Slice(app_metadata_).ToString(/* hex */ true);
buf << kMetaDataPrefix.ToString() << hex_encoded_metadata << "\n";
}
buf << files_.size() << "\n";
for (const auto& file : files_) {
// use crc32c for now, switch to something else if needed
// WART: The checksums are crc32c, not original crc32
buf << file->filename << " crc32 " << ChecksumHexToInt32(file->checksum_hex)
<< "\n";
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
s = backup_meta_file->Append(Slice(buf.str()));
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
if (s.ok() && sync) {
s = backup_meta_file->Sync();
}
if (s.ok()) {
s = backup_meta_file->Close();
}
if (s.ok()) {
s = env_->RenameFile(meta_tmp_filename_, meta_filename_);
[RocksDB] BackupableDB Summary: In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you. Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes. There are multiple things you can configure: 1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like. 2. sync - if true, it *guarantees* backup consistency on machine reboot 3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files. 4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup. 5. More things you can find in BackupableDBOptions Here is the directory structure I use: backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot 0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files All the files are ref counted and deleted immediatelly when they get out of scope. Some other stuff in this diff: 1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do. 2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB. Test Plan: I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff. Also, `make asan_check` Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 23:06:52 +01:00
}
return s;
}
// -------- BackupEngineReadOnlyImpl ---------
class BackupEngineReadOnlyImpl : public BackupEngineReadOnly {
public:
BackupEngineReadOnlyImpl(const BackupableDBOptions& options, Env* db_env)
: backup_engine_(new BackupEngineImpl(options, db_env, true)) {}
2014-04-26 23:21:39 +02:00
~BackupEngineReadOnlyImpl() override {}
// The returned BackupInfos are in chronological order, which means the
// latest backup comes last.
void GetBackupInfo(std::vector<BackupInfo>* backup_info) override {
backup_engine_->GetBackupInfo(backup_info);
}
void GetCorruptedBackups(std::vector<BackupID>* corrupt_backup_ids) override {
backup_engine_->GetCorruptedBackups(corrupt_backup_ids);
}
using BackupEngineReadOnly::RestoreDBFromBackup;
Status RestoreDBFromBackup(const RestoreOptions& options, BackupID backup_id,
const std::string& db_dir,
const std::string& wal_dir) override {
return backup_engine_->RestoreDBFromBackup(options, backup_id, db_dir,
wal_dir);
}
using BackupEngineReadOnly::RestoreDBFromLatestBackup;
Status RestoreDBFromLatestBackup(const RestoreOptions& options,
const std::string& db_dir,
const std::string& wal_dir) override {
return backup_engine_->RestoreDBFromLatestBackup(options, db_dir, wal_dir);
}
Status VerifyBackup(BackupID backup_id,
bool verify_with_checksum = false) override {
return backup_engine_->VerifyBackup(backup_id, verify_with_checksum);
}
Status Initialize() { return backup_engine_->Initialize(); }
private:
2014-04-26 23:21:39 +02:00
std::unique_ptr<BackupEngineImpl> backup_engine_;
};
Status BackupEngineReadOnly::Open(const BackupableDBOptions& options, Env* env,
BackupEngineReadOnly** backup_engine_ptr) {
if (options.destroy_old_data) {
return Status::InvalidArgument(
"Can't destroy old data with ReadOnly BackupEngine");
}
std::unique_ptr<BackupEngineReadOnlyImpl> backup_engine(
new BackupEngineReadOnlyImpl(options, env));
auto s = backup_engine->Initialize();
if (!s.ok()) {
*backup_engine_ptr = nullptr;
return s;
}
*backup_engine_ptr = backup_engine.release();
return Status::OK();
}
} // namespace ROCKSDB_NAMESPACE
#endif // ROCKSDB_LITE