Commit Graph

477 Commits

Author SHA1 Message Date
Maysam Yabandeh
718c1c9c1f Pass manual_wal_flush also to the first wal file
Summary:
Currently manual_wal_flush if set in the options will be used only for the wal files created during wal switch. The configuration thus does not affect the first wal file. The patch fixes that and also update the related unit tests.
This PR is built on top of https://github.com/facebook/rocksdb/pull/3756
Closes https://github.com/facebook/rocksdb/pull/3824

Differential Revision: D7909153

Pulled By: maysamyabandeh

fbshipit-source-id: 024ed99d2555db06bf096c902b998e432bb7b9ce
2018-05-14 10:57:56 -07:00
Siying Dong
d59549298f Skip deleted WALs during recovery
Summary:
This patch record min log number to keep to the manifest while flushing SST files to ignore them and any WAL older than them during recovery. This is to avoid scenarios when we have a gap between the WAL files are fed to the recovery procedure. The gap could happen by for example out-of-order WAL deletion. Such gap could cause problems in 2PC recovery where the prepared and commit entry are placed into two separate WAL and gap in the WALs could result into not processing the WAL with the commit entry and hence breaking the 2PC recovery logic.

Before the commit, for 2PC case, we determined which log number to keep in FindObsoleteFiles(). We looked at the earliest logs with outstanding prepare entries, or prepare entries whose respective commit or abort are in memtable. With the commit, the same calculation is done while we apply the SST flush. Just before installing the flush file, we precompute the earliest log file to keep after the flush finishes using the same logic (but skipping the memtables just flushed), record this information to the manifest entry for this new flushed SST file. This pre-computed value is also remembered in memory, and will later be used to determine whether a log file can be deleted. This value is unlikely to change until next flush because the commit entry will stay in memtable. (In WritePrepared, we could have removed the older log files as soon as all prepared entries are committed. It's not yet done anyway. Even if we do it, the only thing we loss with this new approach is earlier log deletion between two flushes, which does not guarantee to happen anyway because the obsolete file clean-up function is only executed after flush or compaction)

This min log number to keep is stored in the manifest using the safely-ignore customized field of AddFile entry, in order to guarantee that the DB generated using newer release can be opened by previous releases no older than 4.2.
Closes https://github.com/facebook/rocksdb/pull/3765

Differential Revision: D7747618

Pulled By: siying

fbshipit-source-id: d00c92105b4f83852e9754a1b70d6b64cb590729
2018-05-03 15:43:09 -07:00
Huachao Huang
ed7a95b28c Add max_subcompactions as a compaction option
Summary:
Sometimes we want to compact files as fast as possible, but don't want to set a large `max_subcompactions` in the `DBOptions` by default.
I add a `max_subcompactions` options to `CompactionOptions` so that we can choose a proper concurrency dynamically.
Closes https://github.com/facebook/rocksdb/pull/3775

Differential Revision: D7792357

Pulled By: ajkr

fbshipit-source-id: 94f54c3784dce69e40a229721a79a97e80cd6a6c
2018-04-27 11:57:39 -07:00
Siying Dong
63c965cdb4 Sync parent directory after deleting a file in delete scheduler
Summary:
sync parent directory after deleting a file in delete scheduler. Otherwise, trim speed may not be as smooth as what we want.
Closes https://github.com/facebook/rocksdb/pull/3767

Differential Revision: D7760136

Pulled By: siying

fbshipit-source-id: ec131d53b61953f09c60d67e901e5eeb2716b05f
2018-04-26 13:58:20 -07:00
Maysam Yabandeh
bde1c1a72a WritePrepared Txn: add stats
Summary:
Adding some stats that would be helpful to monitor if the DB has gone to unlikely stats that would hurt the performance. These are mostly when we end up needing to acquire a mutex.
Closes https://github.com/facebook/rocksdb/pull/3683

Differential Revision: D7529393

Pulled By: maysamyabandeh

fbshipit-source-id: f7d36279a8f39bd84d8ddbf64b5c97f670c5d6d9
2018-04-07 21:56:42 -07:00
Phani Shekhar Mantripragada
446b32cfc3 Support for Column family specific paths.
Summary:
In this change, an option to set different paths for different column families is added.
This option is set via cf_paths setting of ColumnFamilyOptions. This option will work in a similar fashion to db_paths setting. Cf_paths is a vector of Dbpath values which contains a pair of the absolute path and target size. Multiple levels in a Column family can go to different paths if cf_paths has more than one path.
To maintain backward compatibility, if cf_paths is not specified for a column family, db_paths setting will be used. Note that, if db_paths setting is also not specified, RocksDB already has code to use db_name as the only path.

Changes :
1) A new member "cf_paths" is added to ImmutableCfOptions. This is set, based on cf_paths setting of ColumnFamilyOptions and db_paths setting of ImmutableDbOptions.  This member is used to identify the path information whenever files are accessed.
2) Validation checks are added for cf_paths setting based on existing checks for db_paths setting.
3) DestroyDB, PurgeObsoleteFiles etc. are edited to support multiple cf_paths.
4) Unit tests are added appropriately.
Closes https://github.com/facebook/rocksdb/pull/3102

Differential Revision: D6951697

Pulled By: ajkr

fbshipit-source-id: 60d2262862b0a8fd6605b09ccb0da32bb331787d
2018-04-05 19:58:20 -07:00
Maysam Yabandeh
b225de7e10 WritePrepared Txn: smallest_prepare optimization
Summary:
The is an optimization to reduce lookup in the CommitCache when querying IsInSnapshot. The optimization takes the smallest uncommitted data at the time that the snapshot was taken and if the sequence number of the read data is lower than that number it assumes the data as committed.
To implement this optimization two changes are required: i) The AddPrepared function must be called sequentially to avoid out of order insertion in the PrepareHeap (otherwise the top of the heap does not indicate the smallest prepare in future too), ii) non-2PC transactions also call AddPrepared if they do not commit in one step.
Closes https://github.com/facebook/rocksdb/pull/3649

Differential Revision: D7388630

Pulled By: maysamyabandeh

fbshipit-source-id: b79506238c17467d590763582960d4d90181c600
2018-04-02 20:27:41 -07:00
Amy Tai
1579626d0d Enable cancelling manual compactions if they hit the sfm size limit
Summary:
Manual compactions should be cancelled, just like scheduled compactions are cancelled, if sfm->EnoughRoomForCompaction is not true.
Closes https://github.com/facebook/rocksdb/pull/3670

Differential Revision: D7457683

Pulled By: amytai

fbshipit-source-id: 669b02fdb707f75db576d03d2c818fb98d1876f5
2018-04-02 19:58:04 -07:00
Maysam Yabandeh
0377ff9dea WritePrepared Txn: make recoverable state visible after flush
Summary:
Currently if the CommitTimeWriteBatch is set to be used only as a state that is required only for recovery , the user cannot see that in DB until it is restarted. This while the state is already inserted into the DB after the memtable flush. It would be useful for debugging if make this state visible to the user after the flush by committing it. The patch does it by a invoking a callback that does the commit on the recoverable state.
Closes https://github.com/facebook/rocksdb/pull/3661

Differential Revision: D7424577

Pulled By: maysamyabandeh

fbshipit-source-id: 137f9408662f0853938b33fa440f27f04c1bbf5c
2018-03-28 12:12:08 -07:00
Yanqin Jin
1f5def1653 Fix race condition causing double deletion of ssts
Summary:
Possible interleaved execution of background compaction thread calling `FindObsoleteFiles (no full scan) / PurgeObsoleteFiles` and user thread calling `FindObsoleteFiles (full scan) / PurgeObsoleteFiles` can lead to race condition on which RocksDB attempts to delete a file twice. The second attempt will fail and return `IO error`. This may occur to other files,  but this PR targets sst.
Also add a unit test to verify that this PR fixes the issue.

The newly added unit test `obsolete_files_test` has a test case for this scenario, implemented in `ObsoleteFilesTest#RaceForObsoleteFileDeletion`. `TestSyncPoint`s are used to coordinate the interleaving the `user_thread` and background compaction thread. They execute as follows
```
timeline              user_thread                background_compaction thread
t1   |                                          FindObsoleteFiles(full_scan=false)
t2   |     FindObsoleteFiles(full_scan=true)
t3   |                                          PurgeObsoleteFiles
t4   |     PurgeObsoleteFiles
     V
```
When `user_thread` invokes `FindObsoleteFiles` with full scan, it collects ALL files in RocksDB directory, including the ones that background compaction thread have collected in its job context. Then `user_thread` will see an IO error when trying to delete these files in `PurgeObsoleteFiles` because background compaction thread has already deleted the file in `PurgeObsoleteFiles`.
To fix this, we make RocksDB remember which (SST) files have been found by threads after calling `FindObsoleteFiles` (see `DBImpl#files_grabbed_for_purge_`). Therefore, when another thread calls `FindObsoleteFiles` with full scan, it will not collect such files.

ajkr could you take a look and comment? Thanks!
Closes https://github.com/facebook/rocksdb/pull/3638

Differential Revision: D7384372

Pulled By: riversand963

fbshipit-source-id: 01489516d60012e722ee65a80e1449e589ce26d3
2018-03-28 10:29:59 -07:00
Maysam Yabandeh
35a4469bbf Fix race condition via concurrent FlushWAL
Summary:
Currently log_writer->AddRecord in WriteImpl is protected from concurrent calls via FlushWAL only if two_write_queues_ option is set. The patch fixes the problem by i) skip log_writer->AddRecord in FlushWAL if manual_wal_flush is not set, ii) protects log_writer->AddRecord in WriteImpl via log_write_mutex_ if manual_wal_flush_ is set but two_write_queues_ is not.

Fixes #3599
Closes https://github.com/facebook/rocksdb/pull/3656

Differential Revision: D7405608

Pulled By: maysamyabandeh

fbshipit-source-id: d6cc265051c77ae49c7c6df4f427350baaf46934
2018-03-26 16:29:56 -07:00
Zhongyi Xie
1cbc96d236 FlushReason improvement
Summary:
Right now flush reason "SuperVersion Change" covers a few different scenarios which is a bit vague. For example, the following db_bench job should trigger "Write Buffer Full"

> $ TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -write_buffer_size=1048576 -target_file_size_base=1048576 -max_bytes_for_level_base=4194304
$ grep 'flush_reason' /dev/shm/dbbench/LOG
...
2018/03/06-17:30:42.543638 7f2773b99700 EVENT_LOG_v1 {"time_micros": 1520386242543634, "job": 192, "event": "flush_started", "num_memtables": 1, "num_entries": 7006, "num_deletes": 0, "memory_usage": 1018024, "flush_reason": "SuperVersion Change"}
2018/03/06-17:30:42.569541 7f2773b99700 EVENT_LOG_v1 {"time_micros": 1520386242569536, "job": 193, "event": "flush_started", "num_memtables": 1, "num_entries": 7006, "num_deletes": 0, "memory_usage": 1018104, "flush_reason": "SuperVersion Change"}
2018/03/06-17:30:42.596396 7f2773b99700 EVENT_LOG_v1 {"time_micros": 1520386242596392, "job": 194, "event": "flush_started", "num_memtables": 1, "num_entries": 7008, "num_deletes": 0, "memory_usage": 1018048, "flush_reason": "SuperVersion Change"}
2018/03/06-17:30:42.622444 7f2773b99700 EVENT_LOG_v1 {"time_micros": 1520386242622440, "job": 195, "event": "flush_started", "num_memtables": 1, "num_entries": 7006, "num_deletes": 0, "memory_usage": 1018104, "flush_reason": "SuperVersion Change"}

With the fix:
> 2018/03/19-14:40:02.341451 7f11dc257700 EVENT_LOG_v1 {"time_micros": 1521495602341444, "job": 98, "event": "flush_started", "num_memtables": 1, "num_entries": 7009, "num_deletes": 0, "memory_usage": 1018008, "flush_reason": "Write Buffer Full"}
2018/03/19-14:40:02.379655 7f11dc257700 EVENT_LOG_v1 {"time_micros": 1521495602379642, "job": 100, "event": "flush_started", "num_memtables": 1, "num_entries": 7006, "num_deletes": 0, "memory_usage": 1018016, "flush_reason": "Write Buffer Full"}
2018/03/19-14:40:02.418479 7f11dc257700 EVENT_LOG_v1 {"time_micros": 1521495602418474, "job": 101, "event": "flush_started", "num_memtables": 1, "num_entries": 7009, "num_deletes": 0, "memory_usage": 1018104, "flush_reason": "Write Buffer Full"}
2018/03/19-14:40:02.455084 7f11dc257700 EVENT_LOG_v1 {"time_micros": 1521495602455079, "job": 102, "event": "flush_started", "num_memtables": 1, "num_entries": 7009, "num_deletes": 0, "memory_usage": 1018048, "flush_reason": "Write Buffer Full"}
2018/03/19-14:40:02.492293 7f11dc257700 EVENT_LOG_v1 {"time_micros": 1521495602492288, "job": 104, "event": "flush_started", "num_memtables": 1, "num_entries": 7007, "num_deletes": 0, "memory_usage": 1018056, "flush_reason": "Write Buffer Full"}
2018/03/19-14:40:02.528720 7f11dc257700 EVENT_LOG_v1 {"time_micros": 1521495602528715, "job": 105, "event": "flush_started", "num_memtables": 1, "num_entries": 7006, "num_deletes": 0, "memory_usage": 1018104, "flush_reason": "Write Buffer Full"}
2018/03/19-14:40:02.566255 7f11dc257700 EVENT_LOG_v1 {"time_micros": 1521495602566238, "job": 107, "event": "flush_started", "num_memtables": 1, "num_entries": 7009, "num_deletes": 0, "memory_usage": 1018112, "flush_reason": "Write Buffer Full"}
Closes https://github.com/facebook/rocksdb/pull/3627

Differential Revision: D7328772

Pulled By: miasantreble

fbshipit-source-id: 67c94065fbdd36930f09930aad0aaa6d2c152bb8
2018-03-22 18:42:18 -07:00
Andrew Kryczka
4d51feab0b Rename function for handling WAL write error
Summary:
It was misnamed. It actually updates `bg_error_` if `PreprocessWrite()` or `WriteToWAL()` fail, not related to the user callback.
Closes https://github.com/facebook/rocksdb/pull/3485

Differential Revision: D6955787

Pulled By: ajkr

fbshipit-source-id: bd7afc3fdb7a52830c021cbfc25fcbc3ab7d5e10
2018-03-22 15:58:39 -07:00
Maysam Yabandeh
7429b20e39 WritePrepared Txn: fix race condition on publishing seq
Summary:
This commit fixes a race condition on calling SetLastPublishedSequence. The function must be called only from the 2nd write queue when two_write_queues is enabled. However there was a bug that would also call it from the main write queue if CommitTimeWriteBatch is provided to the commit request and yet use_only_the_last_commit_time_batch_for_recovery optimization is not enabled. To fix that we penalize the commit request in such cases by doing an additional write solely to publish the seq number from the 2nd queue.
Closes https://github.com/facebook/rocksdb/pull/3641

Differential Revision: D7361508

Pulled By: maysamyabandeh

fbshipit-source-id: bf8f7a27e5cccf5425dccbce25eb0032e8e5a4d7
2018-03-22 14:43:36 -07:00
Niv Dayan
da82aab126 allowing CompactFiles to return new file names
Summary:
This is a small API extension to allow the CompactFiles method to return the names of files that were created during the compaction.
Closes https://github.com/facebook/rocksdb/pull/3608

Differential Revision: D7275789

Pulled By: siying

fbshipit-source-id: 1ec0c3954a0f10cd877efb5f29f9be6c7b59e9ba
2018-03-15 11:58:12 -07:00
Bruce Mitchener
a3a3f5497c Fix some typos in comments and docs.
Summary: Closes https://github.com/facebook/rocksdb/pull/3568

Differential Revision: D7170953

Pulled By: siying

fbshipit-source-id: 9cfb8dd88b7266da920c0e0c1e10fb2c5af0641c
2018-03-08 10:27:25 -08:00
amytai
0a3db28d98 Disallow compactions if there isn't enough free space
Summary:
This diff handles cases where compaction causes an ENOSPC error.
This does not handle corner cases where another background job is started while compaction is running, and the other background job triggers ENOSPC, although we do allow the user to provision for these background jobs with SstFileManager::SetCompactionBufferSize.
It also does not handle the case where compaction has finished and some other background job independently triggers ENOSPC.

Usage: Functionality is inside SstFileManager. In particular, users should set SstFileManager::SetMaxAllowedSpaceUsage, which is the reference highwatermark for determining whether to cancel compactions.
Closes https://github.com/facebook/rocksdb/pull/3449

Differential Revision: D7016941

Pulled By: amytai

fbshipit-source-id: 8965ab8dd8b00972e771637a41b4e6c645450445
2018-03-06 16:27:54 -08:00
Maysam Yabandeh
680864ae54 WritePrepared Txn: Fix bug with duplicate keys during recovery
Summary:
Fix the following bugs:
- During recovery a duplicate key was inserted twice into the write batch of the recovery transaction,
once when the memtable returns false (because it was duplicates) and once for the 2nd attempt. This would result into different SubBatch count measured when the recovered transactions is committing.
- If a cf is flushed during recovery the memtable is not available to assist in detecting the duplicate key. This could result into not advancing the sequence number when iterating over duplicate keys of a flushed cf and hence inserting the next key with the wrong sequence number.
- SubBacthCounter would reset the comparator to default comparator after the first duplicate key. The 2nd duplicate key hence would have gone through a wrong comparator and not being detected.
Closes https://github.com/facebook/rocksdb/pull/3562

Differential Revision: D7149440

Pulled By: maysamyabandeh

fbshipit-source-id: 91ec317b165f363f5d11ff8b8c47c81cebb8ed77
2018-03-05 10:57:59 -08:00
Maysam Yabandeh
d060421c77 Fix a leak in prepared_section_completed_
Summary:
The zeroed entries were not removed from prepared_section_completed_ map. This patch adds a unit test to show the problem and fixes that by refactoring the code. The new code is more efficient since i) it uses two separate mutex to avoid contention between commit and prepare threads, ii) it uses a sorted vector for maintaining uniq log entires with prepare which avoids a very large heap with many duplicate entries.
Closes https://github.com/facebook/rocksdb/pull/3545

Differential Revision: D7106071

Pulled By: maysamyabandeh

fbshipit-source-id: b3ae17cb6cd37ef10b6b35e0086c15c758768a48
2018-03-01 20:41:56 -08:00
Yi Wu
bf937cf15b Add "rocksdb.live-sst-files-size" DB property
Summary:
Add "rocksdb.live-sst-files-size" DB property which only include files of latest version. Existing "rocksdb.total-sst-files-size" include files from all versions and thus include files that's obsolete but not yet deleted. I'm going to use this new property to cap blob db sst + blob files size.
Closes https://github.com/facebook/rocksdb/pull/3548

Differential Revision: D7116939

Pulled By: yiwu-arbug

fbshipit-source-id: c6a52e45ce0f24ef78708156e1a923c1dd6bc79a
2018-03-01 18:01:10 -08:00
leviathan1995
ec5843dca9 Comment typo
Summary: Closes https://github.com/facebook/rocksdb/pull/3546

Differential Revision: D7111708

Pulled By: ajkr

fbshipit-source-id: 522a4a00eb3e34c73afcb86c1f75cd2e90e7608d
2018-02-28 09:56:45 -08:00
Anand Ananthabhotla
dfbe52e099 Fix the Logger::Close() and DBImpl::Close() design pattern
Summary:
The recent Logger::Close() and DBImpl::Close() implementation rely on
calling the CloseImpl() virtual function from the destructor, which will
not work. Refactor the implementation to have a private close helper
function in derived classes that can be called by both CloseImpl() and
the destructor.
Closes https://github.com/facebook/rocksdb/pull/3528

Reviewed By: gfosco

Differential Revision: D7049303

Pulled By: anand1976

fbshipit-source-id: 76a64cbf403209216dfe4864ecf96b5d7f3db9f4
2018-02-23 13:57:26 -08:00
Andrew Kryczka
ee1c802675 Add delay before flush in CompactRange to avoid write stalling
Summary:
- Refactored logic for checking write stall condition to a helper function: `GetWriteStallConditionAndCause`. Now it is decoupled from the logic for updating WriteController / stats in `RecalculateWriteStallConditions`, so we can reuse it for predicting whether write stall will occur.
- Updated `CompactRange` to first check whether the one additional immutable memtable / L0 file would cause stalling before it flushes. If so, it waits until that is no longer true.
- Updated `bg_cv_` to be signaled on `SetOptions` calls. The stall conditions `CompactRange` cares about can change when (1) flush finishes, (2) compaction finishes, or (3) options dynamically change. The cv was already signaled for (1) and (2) but not yet for (3).
Closes https://github.com/facebook/rocksdb/pull/3381

Differential Revision: D6754983

Pulled By: ajkr

fbshipit-source-id: 5613e03f1524df7192dc6ae885d40fd8f091d972
2018-02-12 15:42:47 -08:00
Zhongyi Xie
945f618ba5 log flush reason for better debugging experience
Summary:
It's always a mystery from the logs why flush was triggered -- user triggered it manually, WriteBufferManager triggered it,  logs were full, write buffer was full, etc.
This PR logs Flush reason whenever a flush is scheduled.
Closes https://github.com/facebook/rocksdb/pull/3401

Differential Revision: D6788142

Pulled By: miasantreble

fbshipit-source-id: a867e54d493c06adf5172bd36a180fb3faae3511
2018-02-09 12:12:43 -08:00
Maysam Yabandeh
88d8b2a2f5 WritePrepared Txn: Duplicate Keys, Txn Part
Summary:
This patch takes advantage of memtable being able to detect duplicate <key,seq> and returning TryAgain to handle duplicate keys in WritePrepared Txns. Through WriteBatchWithIndex's index it detects existence of at least a duplicate key in the write batch. If duplicate key was reported, it then pays the cost of counting the number of sub-patches by iterating over the write batch and pass it to DBImpl::Write. DB will make use of the provided batch_count to assign proper sequence numbers before sending them to the WAL. When later inserting the batch to the memtable, it increases the seq each time memtbale reports a duplicate (a sub-patch in our counting) and tries again.
Closes https://github.com/facebook/rocksdb/pull/3455

Differential Revision: D6873699

Pulled By: maysamyabandeh

fbshipit-source-id: db8487526c3a5dc1ddda0ea49f0f979b26ae648d
2018-02-05 18:43:24 -08:00
Anand Ananthabhotla
4b124fb9d3 Handle error return from WriteBuffer()
Summary:
There are a couple of places where we swallow any error from
WriteBuffer() - in SwitchMemtable() and DBImpl::CloseImpl(). Propagate
the error up in those cases rather than ignoring it.
Closes https://github.com/facebook/rocksdb/pull/3404

Differential Revision: D6879954

Pulled By: anand1976

fbshipit-source-id: 2ef88b554be5286b0a8bad7384ba17a105395bdb
2018-02-05 13:59:34 -08:00
Huachao Huang
ab43ff58b5 Delete files in multiple ranges at once
Summary:
Using `DeleteFilesInRange` to delete files in a lot of ranges can be slow, because
`VersionSet::LogAndApply` is expensive.

This PR adds a new `DeleteFilesInRange` function to delete files in multiple
ranges at once.

Close https://github.com/facebook/rocksdb/issues/2951
Closes https://github.com/facebook/rocksdb/pull/3431

Differential Revision: D6849228

Pulled By: ajkr

fbshipit-source-id: daeedcabd8def4b1d9ee95a58266dee77b5d68cb
2018-01-30 13:56:39 -08:00
Yi Wu
f1cb83fcf4 Fix Flush() keep waiting after flush finish
Summary:
Flush() call could be waiting indefinitely if min_write_buffer_number_to_merge is used. Consider the sequence:
1. User call Flush() with flush_options.wait = true
2. The manual flush started in the background
3. New memtable become immutable because of writes. The new memtable will not trigger flush if min_write_buffer_number_to_merge is not reached.
4. The manual flush finish.

Because of the new memtable created at step 3 not being flush, previous logic of WaitForFlushMemTable() keep waiting, despite the memtables it intent to flush has been flushed.

Here instead of checking if there are any more memtables to flush, WaitForFlushMemTable() also check the id of the earliest memtable. If the id is larger than that of latest memtable at the time flush was initiated, it means all the memtable at the time of flush start has all been flush.
Closes https://github.com/facebook/rocksdb/pull/3378

Differential Revision: D6746789

Pulled By: yiwu-arbug

fbshipit-source-id: 35e698f71c7f90b06337a93e6825f4ea3b619bfa
2018-01-18 17:45:16 -08:00
Andrew Kryczka
46e599fc6b fix live WALs purged while file deletions disabled
Summary:
When calling `DisableFileDeletions` followed by `GetSortedWalFiles`, we guarantee the files returned by the latter call won't be deleted until after file deletions are re-enabled. However, `GetSortedWalFiles` didn't omit files already planned for deletion via `PurgeObsoleteFiles`, so the guarantee could be broken.

We fix it by making `GetSortedWalFiles` wait for the number of pending purges to hit zero if file deletions are disabled. This condition is eventually met since `PurgeObsoleteFiles` is guaranteed to be called for the existing pending purges, and new purges cannot be scheduled while file deletions are disabled. Once the condition is met, `GetSortedWalFiles` simply returns the content of DB and archive directories, which nobody can delete (except for deletion scheduler, for which I plan to fix this bug later) until deletions are re-enabled.
Closes https://github.com/facebook/rocksdb/pull/3341

Differential Revision: D6681131

Pulled By: ajkr

fbshipit-source-id: 90b1e2f2362ea9ef715623841c0826611a817634
2018-01-17 17:42:04 -08:00
Anand Ananthabhotla
d0f1b49ab6 Add a Close() method to DB to return status when closing a db
Summary:
Currently, the only way to close an open DB is to destroy the DB
object. There is no way for the caller to know the status. In one
instance, the destructor encountered an error due to failure to
close a log file on HDFS. In order to prevent silent failures, we add
DB::Close() that calls CloseImpl() which must be implemented by its
descendants.
The main failure point in the destructor is closing the log file. This
patch also adds a Close() entry point to Logger in order to get status.
When DBOptions::info_log is allocated and owned by the DBImpl, it is
explicitly closed by DBImpl::CloseImpl().
Closes https://github.com/facebook/rocksdb/pull/3348

Differential Revision: D6698158

Pulled By: anand1976

fbshipit-source-id: 9468e2892553eb09c4c41b8723f590c0dbd8ab7d
2018-01-16 11:08:57 -08:00
Andrew Kryczka
0f0d2ab95a fix DBImpl instance variable naming
Summary:
got confused while reading `FindObsoleteFiles` due to thinking it's a local variable, so renamed it properly
Closes https://github.com/facebook/rocksdb/pull/3342

Differential Revision: D6684797

Pulled By: ajkr

fbshipit-source-id: a4df0aae1cccce99d4dd4d164aadc85b17707132
2018-01-09 12:56:58 -08:00
Yi Wu
06149429d9 WritePrepared Txn: Return NotSupported on iterator refresh
Summary:
A proper implementation of Iterator::Refresh() for WritePreparedTxnDB would require release and acquire another snapshot. Since MyRocks don't make use of Iterator::Refresh(), we just simply mark it as not supported.
Closes https://github.com/facebook/rocksdb/pull/3290

Differential Revision: D6599931

Pulled By: yiwu-arbug

fbshipit-source-id: 4e1632d967316431424f6e458254ecf9a97567cf
2017-12-18 22:29:30 -08:00
Yi Wu
237b292515 BlobDB: Remove the need to get sequence number per write
Summary:
Previously we store sequence number range of each blob files, and use the sequence number range to check if the file can be possibly visible by a snapshot. But it adds complexity to the code, since the sequence number is only available after a write. (The current implementation get sequence number by calling GetLatestSequenceNumber(), which is wrong.) With the patch, we are not storing sequence number range, and check if snapshot_sequence < obsolete_sequence to decide if the file is visible by a snapshot (previously we check if first_sequence <= snapshot_sequence < obsolete_sequence).
Closes https://github.com/facebook/rocksdb/pull/3274

Differential Revision: D6571497

Pulled By: yiwu-arbug

fbshipit-source-id: ca06479dc1fcd8782f6525b62b7762cd47d61909
2017-12-15 13:27:30 -08:00
Maysam Yabandeh
18dcf7f98d WritePrepared Txn: PreReleaseCallback
Summary:
Add PreReleaseCallback to be called at the end of WriteImpl but before publishing the sequence number. The callback is used in WritePrepareTxn to i) update the commit map, ii) update the last published sequence number in the 2nd write queue. It also ensures that all the commits will go to the 2nd queue.
These changes will ensure that the commit map is updated before the sequence number is published and used by reading snapshots. If we use two write queues, the snapshots will use the seq number published by the 2nd queue. If we use one write queue (the default, the snapshots will use the last seq number in the memtable, which also indicates the last published seq number.
Closes https://github.com/facebook/rocksdb/pull/3205

Differential Revision: D6438959

Pulled By: maysamyabandeh

fbshipit-source-id: f8b6c434e94bc5f5ab9cb696879d4c23e2577ab9
2017-11-30 23:50:45 -08:00
Maysam Yabandeh
54b43563be WritePrepared Txn: Refactoring WriteCallback
Summary:
Refactor the logic around WriteCallback in the write path to clarify when and how exactly we advance the sequence number and making sure it is consistent across the code.
Closes https://github.com/facebook/rocksdb/pull/3168

Differential Revision: D6324312

Pulled By: maysamyabandeh

fbshipit-source-id: 9a34f479561fdb2a5d01ef6d37a28908d03bbe33
2017-11-15 08:27:06 -08:00
Maysam Yabandeh
857adf388f WritePrepared Txn: Refactor conf params
Summary:
Summary of changes:
- Move seq_per_batch out of Options
- Rename concurrent_prepare to two_write_queues
- Add allocate_seq_only_for_data_
Closes https://github.com/facebook/rocksdb/pull/3136

Differential Revision: D6304458

Pulled By: maysamyabandeh

fbshipit-source-id: 08e685bfa82bbc41b5b1c5eb7040a8ca6e05e58c
2017-11-10 17:28:12 -08:00
Shaohua Li
eefd75a228 Stream
Summary:
Add a simple policy for NVMe write time life hint
Closes https://github.com/facebook/rocksdb/pull/3095

Differential Revision: D6298030

Pulled By: shligit

fbshipit-source-id: 9a72a42e32e92193af11599eb71f0cf77448e24d
2017-11-10 09:26:24 -08:00
Yi Wu
7bfa88037e Blob DB: fix snapshot handling
Summary:
Blob db will keep blob file if data in the file is visible to an active snapshot. Before this patch it checks whether there is an active snapshot has sequence number greater than the earliest sequence in the file. This is problematic since we take snapshot on every read, if it keep having reads, old blob files will not be cleanup. Change to check if there is an active snapshot falls in the range of [earliest_sequence, obsolete_sequence) where obsolete sequence is
1. if data is relocated to another file by garbage collection, it is the latest sequence at the time garbage collection finish
2. otherwise, it is the latest sequence of the file
Closes https://github.com/facebook/rocksdb/pull/3087

Differential Revision: D6182519

Pulled By: yiwu-arbug

fbshipit-source-id: cdf4c35281f782eb2a9ad6a87b6727bbdff27a45
2017-11-02 15:58:27 -07:00
Mikhail Antonov
7fe3b32896 Added support for differential snapshots
Summary:
The motivation for this PR is to add to RocksDB support for differential (incremental) snapshots, as snapshot of the DB changes between two points in time (one can think of it as diff between to sequence numbers, or the diff D which can be thought of as an SST file or just set of KVs that can be applied to sequence number S1 to get the database to the state at sequence number S2).

This feature would be useful for various distributed storages layers built on top of RocksDB, as it should help reduce resources (time and network bandwidth) needed to recover and rebuilt DB instances as replicas in the context of distributed storages.

From the API standpoint that would like client app requesting iterator between (start seqnum) and current DB state, and reading the "diff".

This is a very draft PR for initial review in the discussion on the approach, i'm going to rework some parts and keep updating the PR.

For now, what's done here according to initial discussions:

Preserving deletes:
 - We want to be able to optionally preserve recent deletes for some defined period of time, so that if a delete came in recently and might need to be included in the next incremental snapshot it would't get dropped by a compaction. This is done by adding new param to Options (preserve deletes flag) and new variable to DB Impl where we keep track of the sequence number after which we don't want to drop tombstones, even if they are otherwise eligible for deletion.
 - I also added a new API call for clients to be able to advance this cutoff seqnum after which we drop deletes; i assume it's more flexible to let clients control this, since otherwise we'd need to keep some kind of timestamp < -- > seqnum mapping inside the DB, which sounds messy and painful to support. Clients could make use of it by periodically calling GetLatestSequenceNumber(), noting the timestamp, doing some calculation and figuring out by how much we need to advance the cutoff seqnum.
 - Compaction codepath in compaction_iterator.cc has been modified to avoid dropping tombstones with seqnum > cutoff seqnum.

Iterator changes:
 - couple params added to ReadOptions, to optionally allow client to request internal keys instead of user keys (so that client can get the latest value of a key, be it delete marker or a put), as well as min timestamp and min seqnum.

TableCache changes:
 - I modified table_cache code to be able to quickly exclude SST files from iterators heep if creation_time on the file is less then iter_start_ts as passed in ReadOptions. That would help a lot in some DB settings (like reading very recent data only or using FIFO compactions), but not so much for universal compaction with more or less long iterator time span.

What's left:

 - Still looking at how to best plug that inside DBIter codepath. So far it seems that FindNextUserKeyInternal only parses values as UserKeys, and iter->key() call generally returns user key. Can we add new API to DBIter as internal_key(), and modify this internal method to optionally set saved_key_ to point to the full internal key? I don't need to store actual seqnum there, but I do need to store type.
Closes https://github.com/facebook/rocksdb/pull/2999

Differential Revision: D6175602

Pulled By: mikhail-antonov

fbshipit-source-id: c779a6696ee2d574d86c69cec866a3ae095aa900
2017-11-01 18:56:43 -07:00
Maysam Yabandeh
17731a43a6 WritePrepared Txn: Optimize for recoverable state
Summary:
GetCommitTimeWriteBatch is currently used to store some state as part of commit in 2PC. In MyRocks it is specifically used to store some data that would be needed only during recovery. So it is not need to be stored in memtable right after each commit.
This patch enables an optimization to write the GetCommitTimeWriteBatch only to the WAL. The batch will be written to memtable during recovery when the WAL is replayed. To cover the case when WAL is deleted after memtable flush, the batch is also buffered and written to memtable right before each memtable flush.
Closes https://github.com/facebook/rocksdb/pull/3071

Differential Revision: D6148023

Pulled By: maysamyabandeh

fbshipit-source-id: 2d09bae5565abe2017c0327421010d5c0d55eaa7
2017-11-01 17:26:46 -07:00
Maysam Yabandeh
63822eb761 Enable two write queues for transactions
Summary:
Enable concurrent_prepare flag for WritePrepared transactions and extend the existing transaction tests with this config.
Closes https://github.com/facebook/rocksdb/pull/3046

Differential Revision: D6106534

Pulled By: maysamyabandeh

fbshipit-source-id: 88c8d21d45bc492beb0a131caea84a2ac5e7d38c
2017-10-23 14:27:04 -07:00
Maysam Yabandeh
7e38238981 WritePrepared Txn: Disable GC during recovery
Summary:
Disables GC during recovery of a WritePrepared txn db to avoid GCing uncommitted key values.
Closes https://github.com/facebook/rocksdb/pull/2980

Differential Revision: D6000191

Pulled By: maysamyabandeh

fbshipit-source-id: fc4d522c643d24ebf043f811fe4ecd0dd0294675
2017-10-18 09:11:50 -07:00
Yi Wu
eaaef91178 Blob DB: Store blob index as kTypeBlobIndex in base db
Summary:
Blob db insert blob index to base db as kTypeBlobIndex type, to tell apart values written by plain rocksdb or blob db. This is to make it possible to migrate from existing rocksdb to blob db.

Also with the patch blob db garbage collection get away from OptimisticTransaction. Instead it use a custom write callback to achieve similar behavior as OptimisticTransaction. This is because we need to pass the is_blob_index flag to DBImpl::Get but OptimisticTransaction don't support it.
Closes https://github.com/facebook/rocksdb/pull/3000

Differential Revision: D6050044

Pulled By: yiwu-arbug

fbshipit-source-id: 61dc72ab9977625e75f78cd968e7d8a3976e3632
2017-10-17 17:28:11 -07:00
Yi Wu
fb4ae4d810 fix DBImpl::NewInternalIterator super-version leak on failure
Summary:
Close #2955
Closes https://github.com/facebook/rocksdb/pull/2960

Differential Revision: D5962872

Pulled By: yiwu-arbug

fbshipit-source-id: a6472d5c015bea3dc476c572ff5a5c90259e6059
2017-10-11 14:57:43 -07:00
Andrew Kryczka
70aa942153 fix file numbers after repair
Summary:
The file numbers assigned post-repair were sometimes smaller than older files' numbers due to `LogAndApply` saving the wrong next file number in the manifest.

- Mark the highest file seen during repair as used before `LogAndApply` so the correct next file number will be stored.
- Renamed `MarkFileNumberUsedDuringRecovery` to `MarkFileNumberUsed` since now it's used during repair in addition to during recovery
- Added `TEST_Current_Next_FileNo` to expose the next file number for the unit test.
Closes https://github.com/facebook/rocksdb/pull/2988

Differential Revision: D6018083

Pulled By: ajkr

fbshipit-source-id: 3f25cbf74439cb8f16dd12af90b67f9f9f75e718
2017-10-10 13:12:37 -07:00
Yi Wu
8c392a31d7 WritePrepared Txn: Iterator
Summary:
On iterator create, take a snapshot, create a ReadCallback and pass the ReadCallback to the underlying DBIter to check if key is committed.
Closes https://github.com/facebook/rocksdb/pull/2981

Differential Revision: D6001471

Pulled By: yiwu-arbug

fbshipit-source-id: 3565c4cdaf25370ba47008b0e0cb65b31dfe79fe
2017-10-09 17:15:28 -07:00
Yi Wu
d1b74b0c82 WritePrepared Txn: Compaction/Flush
Summary:
Update Compaction/Flush to support WritePreparedTxnDB: Add SnapshotChecker which is a proxy to query WritePreparedTxnDB::IsInSnapshot. Pass SnapshotChecker to DBImpl on WritePreparedTxnDB open. CompactionIterator use it to check if a key has been committed and if it is visible to a snapshot. In CompactionIterator:
* check if key has been committed. If not, output uncommitted keys AS-IS.
* use SnapshotChecker to check if key is visible to a snapshot when in need.
* do not output key with seq = 0 if the key is not committed.
Closes https://github.com/facebook/rocksdb/pull/2926

Differential Revision: D5902907

Pulled By: yiwu-arbug

fbshipit-source-id: 945e037fdf0aa652dc5ba0ad879461040baa0320
2017-10-06 10:41:53 -07:00
Adrien Schildknecht
01542400a8 Inform caller when rocksdb is stalling writes
Summary:
Add a new function in Listener to let the caller know when rocksdb
is stalling writes.
Closes https://github.com/facebook/rocksdb/pull/2897

Differential Revision: D5860124

Pulled By: schischi

fbshipit-source-id: ee791606169aa64f772c86f817cebf02624e05e1
2017-10-05 18:11:43 -07:00
Yi Wu
d1cab2b64e Add ValueType::kTypeBlobIndex
Summary:
Add kTypeBlobIndex value type, which will be used by blob db only, to insert a (key, blob_offset) KV pair. The purpose is to
1. Make it possible to open existing rocksdb instance as blob db. Existing value will be of kTypeIndex type, while value inserted by blob db will be of kTypeBlobIndex.
2. Make rocksdb able to detect if the db contains value written by blob db, if so return error.
3. Make it possible to have blob db optionally store value in SST file (with kTypeValue type) or as a blob value (with kTypeBlobIndex type).

The root db (DBImpl) basically pretended kTypeBlobIndex are normal value on write. On Get if is_blob is provided, return whether the value read is of kTypeBlobIndex type, or return Status::NotSupported() status if is_blob is not provided. On scan allow_blob flag is pass and if the flag is true, return wether the value is of kTypeBlobIndex type via iter->IsBlob().

Changes on blob db side will be in a separate patch.
Closes https://github.com/facebook/rocksdb/pull/2886

Differential Revision: D5838431

Pulled By: yiwu-arbug

fbshipit-source-id: 3c5306c62bc13bb11abc03422ec5cbcea1203cca
2017-10-03 09:11:23 -07:00
Maysam Yabandeh
385049baf2 WritePrepared Txn: Recovery
Summary:
Recover txns from the WAL. Also added some unit tests.
Closes https://github.com/facebook/rocksdb/pull/2901

Differential Revision: D5859596

Pulled By: maysamyabandeh

fbshipit-source-id: 6424967b231388093b4effffe0a3b1b7ec8caeb0
2017-09-28 16:56:45 -07:00