rocksdb/table/meta_blocks.cc
Peter Dillinger b4f29f7515 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
2020-09-21 08:05:23 -07:00

537 lines
20 KiB
C++

// 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).
#include "table/meta_blocks.h"
#include <map>
#include <string>
#include "block_fetcher.h"
#include "db/table_properties_collector.h"
#include "file/random_access_file_reader.h"
#include "rocksdb/table.h"
#include "rocksdb/table_properties.h"
#include "table/block_based/block.h"
#include "table/format.h"
#include "table/internal_iterator.h"
#include "table/persistent_cache_helper.h"
#include "table/table_properties_internal.h"
#include "test_util/sync_point.h"
#include "util/coding.h"
namespace ROCKSDB_NAMESPACE {
MetaIndexBuilder::MetaIndexBuilder()
: meta_index_block_(new BlockBuilder(1 /* restart interval */)) {}
void MetaIndexBuilder::Add(const std::string& key,
const BlockHandle& handle) {
std::string handle_encoding;
handle.EncodeTo(&handle_encoding);
meta_block_handles_.insert({key, handle_encoding});
}
Slice MetaIndexBuilder::Finish() {
for (const auto& metablock : meta_block_handles_) {
meta_index_block_->Add(metablock.first, metablock.second);
}
return meta_index_block_->Finish();
}
// Property block will be read sequentially and cached in a heap located
// object, so there's no need for restart points. Thus we set the restart
// interval to infinity to save space.
PropertyBlockBuilder::PropertyBlockBuilder()
: properties_block_(
new BlockBuilder(port::kMaxInt32 /* restart interval */)) {}
void PropertyBlockBuilder::Add(const std::string& name,
const std::string& val) {
props_.insert({name, val});
}
void PropertyBlockBuilder::Add(const std::string& name, uint64_t val) {
assert(props_.find(name) == props_.end());
std::string dst;
PutVarint64(&dst, val);
Add(name, dst);
}
void PropertyBlockBuilder::Add(
const UserCollectedProperties& user_collected_properties) {
for (const auto& prop : user_collected_properties) {
Add(prop.first, prop.second);
}
}
void PropertyBlockBuilder::AddTableProperty(const TableProperties& props) {
TEST_SYNC_POINT_CALLBACK("PropertyBlockBuilder::AddTableProperty:Start",
const_cast<TableProperties*>(&props));
Add(TablePropertiesNames::kRawKeySize, props.raw_key_size);
Add(TablePropertiesNames::kRawValueSize, props.raw_value_size);
Add(TablePropertiesNames::kDataSize, props.data_size);
Add(TablePropertiesNames::kIndexSize, props.index_size);
if (props.index_partitions != 0) {
Add(TablePropertiesNames::kIndexPartitions, props.index_partitions);
Add(TablePropertiesNames::kTopLevelIndexSize, props.top_level_index_size);
}
Add(TablePropertiesNames::kIndexKeyIsUserKey, props.index_key_is_user_key);
Add(TablePropertiesNames::kIndexValueIsDeltaEncoded,
props.index_value_is_delta_encoded);
Add(TablePropertiesNames::kNumEntries, props.num_entries);
Add(TablePropertiesNames::kDeletedKeys, props.num_deletions);
Add(TablePropertiesNames::kMergeOperands, props.num_merge_operands);
Add(TablePropertiesNames::kNumRangeDeletions, props.num_range_deletions);
Add(TablePropertiesNames::kNumDataBlocks, props.num_data_blocks);
Add(TablePropertiesNames::kFilterSize, props.filter_size);
Add(TablePropertiesNames::kFormatVersion, props.format_version);
Add(TablePropertiesNames::kFixedKeyLen, props.fixed_key_len);
Add(TablePropertiesNames::kColumnFamilyId, props.column_family_id);
Add(TablePropertiesNames::kCreationTime, props.creation_time);
Add(TablePropertiesNames::kOldestKeyTime, props.oldest_key_time);
if (props.file_creation_time > 0) {
Add(TablePropertiesNames::kFileCreationTime, props.file_creation_time);
}
if (!props.db_id.empty()) {
Add(TablePropertiesNames::kDbId, props.db_id);
}
if (!props.db_session_id.empty()) {
Add(TablePropertiesNames::kDbSessionId, props.db_session_id);
}
if (!props.filter_policy_name.empty()) {
Add(TablePropertiesNames::kFilterPolicy, props.filter_policy_name);
}
if (!props.comparator_name.empty()) {
Add(TablePropertiesNames::kComparator, props.comparator_name);
}
if (!props.merge_operator_name.empty()) {
Add(TablePropertiesNames::kMergeOperator, props.merge_operator_name);
}
if (!props.prefix_extractor_name.empty()) {
Add(TablePropertiesNames::kPrefixExtractorName,
props.prefix_extractor_name);
}
if (!props.property_collectors_names.empty()) {
Add(TablePropertiesNames::kPropertyCollectors,
props.property_collectors_names);
}
if (!props.column_family_name.empty()) {
Add(TablePropertiesNames::kColumnFamilyName, props.column_family_name);
}
if (!props.compression_name.empty()) {
Add(TablePropertiesNames::kCompression, props.compression_name);
}
if (!props.compression_options.empty()) {
Add(TablePropertiesNames::kCompressionOptions, props.compression_options);
}
}
Slice PropertyBlockBuilder::Finish() {
for (const auto& prop : props_) {
properties_block_->Add(prop.first, prop.second);
}
return properties_block_->Finish();
}
void LogPropertiesCollectionError(
Logger* info_log, const std::string& method, const std::string& name) {
assert(method == "Add" || method == "Finish");
std::string msg =
"Encountered error when calling TablePropertiesCollector::" +
method + "() with collector name: " + name;
ROCKS_LOG_ERROR(info_log, "%s", msg.c_str());
}
bool NotifyCollectTableCollectorsOnAdd(
const Slice& key, const Slice& value, uint64_t file_size,
const std::vector<std::unique_ptr<IntTblPropCollector>>& collectors,
Logger* info_log) {
bool all_succeeded = true;
for (auto& collector : collectors) {
Status s = collector->InternalAdd(key, value, file_size);
all_succeeded = all_succeeded && s.ok();
if (!s.ok()) {
LogPropertiesCollectionError(info_log, "Add" /* method */,
collector->Name());
}
}
return all_succeeded;
}
void NotifyCollectTableCollectorsOnBlockAdd(
const std::vector<std::unique_ptr<IntTblPropCollector>>& collectors,
const uint64_t blockRawBytes, const uint64_t blockCompressedBytesFast,
const uint64_t blockCompressedBytesSlow) {
for (auto& collector : collectors) {
collector->BlockAdd(blockRawBytes, blockCompressedBytesFast,
blockCompressedBytesSlow);
}
}
bool NotifyCollectTableCollectorsOnFinish(
const std::vector<std::unique_ptr<IntTblPropCollector>>& collectors,
Logger* info_log, PropertyBlockBuilder* builder) {
bool all_succeeded = true;
for (auto& collector : collectors) {
UserCollectedProperties user_collected_properties;
Status s = collector->Finish(&user_collected_properties);
all_succeeded = all_succeeded && s.ok();
if (!s.ok()) {
LogPropertiesCollectionError(info_log, "Finish" /* method */,
collector->Name());
} else {
builder->Add(user_collected_properties);
}
}
return all_succeeded;
}
Status ReadProperties(const ReadOptions& read_options,
const Slice& handle_value, RandomAccessFileReader* file,
FilePrefetchBuffer* prefetch_buffer, const Footer& footer,
const ImmutableCFOptions& ioptions,
TableProperties** table_properties, bool verify_checksum,
BlockHandle* ret_block_handle,
CacheAllocationPtr* verification_buf,
bool /*compression_type_missing*/,
MemoryAllocator* memory_allocator) {
assert(table_properties);
Slice v = handle_value;
BlockHandle handle;
if (!handle.DecodeFrom(&v).ok()) {
return Status::InvalidArgument("Failed to decode properties block handle");
}
BlockContents block_contents;
Status s;
PersistentCacheOptions cache_options;
ReadOptions ro = read_options;
ro.verify_checksums = verify_checksum;
BlockFetcher block_fetcher(file, prefetch_buffer, footer, ro, handle,
&block_contents, ioptions, false /* decompress */,
false /*maybe_compressed*/, BlockType::kProperties,
UncompressionDict::GetEmptyDict(), cache_options,
memory_allocator);
s = block_fetcher.ReadBlockContents();
// property block is never compressed. Need to add uncompress logic if we are
// to compress it..
if (!s.ok()) {
return s;
}
Block properties_block(std::move(block_contents));
DataBlockIter iter;
properties_block.NewDataIterator(BytewiseComparator(),
kDisableGlobalSequenceNumber, &iter);
auto new_table_properties = new TableProperties();
// All pre-defined properties of type uint64_t
std::unordered_map<std::string, uint64_t*> predefined_uint64_properties = {
{TablePropertiesNames::kDataSize, &new_table_properties->data_size},
{TablePropertiesNames::kIndexSize, &new_table_properties->index_size},
{TablePropertiesNames::kIndexPartitions,
&new_table_properties->index_partitions},
{TablePropertiesNames::kTopLevelIndexSize,
&new_table_properties->top_level_index_size},
{TablePropertiesNames::kIndexKeyIsUserKey,
&new_table_properties->index_key_is_user_key},
{TablePropertiesNames::kIndexValueIsDeltaEncoded,
&new_table_properties->index_value_is_delta_encoded},
{TablePropertiesNames::kFilterSize, &new_table_properties->filter_size},
{TablePropertiesNames::kRawKeySize, &new_table_properties->raw_key_size},
{TablePropertiesNames::kRawValueSize,
&new_table_properties->raw_value_size},
{TablePropertiesNames::kNumDataBlocks,
&new_table_properties->num_data_blocks},
{TablePropertiesNames::kNumEntries, &new_table_properties->num_entries},
{TablePropertiesNames::kDeletedKeys,
&new_table_properties->num_deletions},
{TablePropertiesNames::kMergeOperands,
&new_table_properties->num_merge_operands},
{TablePropertiesNames::kNumRangeDeletions,
&new_table_properties->num_range_deletions},
{TablePropertiesNames::kFormatVersion,
&new_table_properties->format_version},
{TablePropertiesNames::kFixedKeyLen,
&new_table_properties->fixed_key_len},
{TablePropertiesNames::kColumnFamilyId,
&new_table_properties->column_family_id},
{TablePropertiesNames::kCreationTime,
&new_table_properties->creation_time},
{TablePropertiesNames::kOldestKeyTime,
&new_table_properties->oldest_key_time},
{TablePropertiesNames::kFileCreationTime,
&new_table_properties->file_creation_time},
};
std::string last_key;
for (iter.SeekToFirstOrReport(); iter.Valid(); iter.NextOrReport()) {
s = iter.status();
if (!s.ok()) {
break;
}
auto key = iter.key().ToString();
// properties block should be strictly sorted with no duplicate key.
if (!last_key.empty() &&
BytewiseComparator()->Compare(key, last_key) <= 0) {
s = Status::Corruption("properties unsorted");
break;
}
last_key = key;
auto raw_val = iter.value();
auto pos = predefined_uint64_properties.find(key);
new_table_properties->properties_offsets.insert(
{key, handle.offset() + iter.ValueOffset()});
if (pos != predefined_uint64_properties.end()) {
if (key == TablePropertiesNames::kDeletedKeys ||
key == TablePropertiesNames::kMergeOperands) {
// Insert in user-collected properties for API backwards compatibility
new_table_properties->user_collected_properties.insert(
{key, raw_val.ToString()});
}
// handle predefined rocksdb properties
uint64_t val;
if (!GetVarint64(&raw_val, &val)) {
// skip malformed value
auto error_msg =
"Detect malformed value in properties meta-block:"
"\tkey: " + key + "\tval: " + raw_val.ToString();
ROCKS_LOG_ERROR(ioptions.info_log, "%s", error_msg.c_str());
continue;
}
*(pos->second) = val;
} else if (key == TablePropertiesNames::kDbId) {
new_table_properties->db_id = raw_val.ToString();
} else if (key == TablePropertiesNames::kDbSessionId) {
new_table_properties->db_session_id = raw_val.ToString();
} else if (key == TablePropertiesNames::kFilterPolicy) {
new_table_properties->filter_policy_name = raw_val.ToString();
} else if (key == TablePropertiesNames::kColumnFamilyName) {
new_table_properties->column_family_name = raw_val.ToString();
} else if (key == TablePropertiesNames::kComparator) {
new_table_properties->comparator_name = raw_val.ToString();
} else if (key == TablePropertiesNames::kMergeOperator) {
new_table_properties->merge_operator_name = raw_val.ToString();
} else if (key == TablePropertiesNames::kPrefixExtractorName) {
new_table_properties->prefix_extractor_name = raw_val.ToString();
} else if (key == TablePropertiesNames::kPropertyCollectors) {
new_table_properties->property_collectors_names = raw_val.ToString();
} else if (key == TablePropertiesNames::kCompression) {
new_table_properties->compression_name = raw_val.ToString();
} else if (key == TablePropertiesNames::kCompressionOptions) {
new_table_properties->compression_options = raw_val.ToString();
} else {
// handle user-collected properties
new_table_properties->user_collected_properties.insert(
{key, raw_val.ToString()});
}
}
if (s.ok()) {
*table_properties = new_table_properties;
if (ret_block_handle != nullptr) {
*ret_block_handle = handle;
}
if (verification_buf != nullptr) {
size_t len = static_cast<size_t>(handle.size() + kBlockTrailerSize);
*verification_buf =
ROCKSDB_NAMESPACE::AllocateBlock(len, memory_allocator);
if (verification_buf->get() != nullptr) {
memcpy(verification_buf->get(), block_contents.data.data(), len);
}
}
} else {
delete new_table_properties;
}
return s;
}
Status ReadTableProperties(RandomAccessFileReader* file, uint64_t file_size,
uint64_t table_magic_number,
const ImmutableCFOptions& ioptions,
TableProperties** properties,
bool compression_type_missing,
MemoryAllocator* memory_allocator,
FilePrefetchBuffer* prefetch_buffer) {
// -- Read metaindex block
Footer footer;
IOOptions opts;
auto s = ReadFooterFromFile(opts, file, prefetch_buffer, file_size, &footer,
table_magic_number);
if (!s.ok()) {
return s;
}
auto metaindex_handle = footer.metaindex_handle();
BlockContents metaindex_contents;
ReadOptions read_options;
read_options.verify_checksums = false;
PersistentCacheOptions cache_options;
BlockFetcher block_fetcher(
file, prefetch_buffer, footer, read_options, metaindex_handle,
&metaindex_contents, ioptions, false /* decompress */,
false /*maybe_compressed*/, BlockType::kMetaIndex,
UncompressionDict::GetEmptyDict(), cache_options, memory_allocator);
s = block_fetcher.ReadBlockContents();
if (!s.ok()) {
return s;
}
// property blocks are never compressed. Need to add uncompress logic if we
// are to compress it.
Block metaindex_block(std::move(metaindex_contents));
std::unique_ptr<InternalIterator> meta_iter(metaindex_block.NewDataIterator(
BytewiseComparator(), kDisableGlobalSequenceNumber));
// -- Read property block
bool found_properties_block = true;
s = SeekToPropertiesBlock(meta_iter.get(), &found_properties_block);
if (!s.ok()) {
return s;
}
TableProperties table_properties;
if (found_properties_block == true) {
s = ReadProperties(
read_options, meta_iter->value(), file, prefetch_buffer, footer,
ioptions, properties, false /* verify_checksum */,
nullptr /* ret_block_hanel */, nullptr /* ret_block_contents */,
compression_type_missing, memory_allocator);
} else {
s = Status::NotFound();
}
return s;
}
Status FindMetaBlock(InternalIterator* meta_index_iter,
const std::string& meta_block_name,
BlockHandle* block_handle) {
meta_index_iter->Seek(meta_block_name);
if (meta_index_iter->status().ok() && meta_index_iter->Valid() &&
meta_index_iter->key() == meta_block_name) {
Slice v = meta_index_iter->value();
return block_handle->DecodeFrom(&v);
} else {
return Status::Corruption("Cannot find the meta block", meta_block_name);
}
}
Status FindMetaBlock(RandomAccessFileReader* file, uint64_t file_size,
uint64_t table_magic_number,
const ImmutableCFOptions& ioptions,
const std::string& meta_block_name,
BlockHandle* block_handle,
bool /*compression_type_missing*/,
MemoryAllocator* memory_allocator) {
Footer footer;
IOOptions opts;
auto s = ReadFooterFromFile(opts, file, nullptr /* prefetch_buffer */,
file_size, &footer, table_magic_number);
if (!s.ok()) {
return s;
}
auto metaindex_handle = footer.metaindex_handle();
BlockContents metaindex_contents;
ReadOptions read_options;
read_options.verify_checksums = false;
PersistentCacheOptions cache_options;
BlockFetcher block_fetcher(
file, nullptr /* prefetch_buffer */, footer, read_options,
metaindex_handle, &metaindex_contents, ioptions,
false /* do decompression */, false /*maybe_compressed*/,
BlockType::kMetaIndex, UncompressionDict::GetEmptyDict(), cache_options,
memory_allocator);
s = block_fetcher.ReadBlockContents();
if (!s.ok()) {
return s;
}
// meta blocks are never compressed. Need to add uncompress logic if we are to
// compress it.
Block metaindex_block(std::move(metaindex_contents));
std::unique_ptr<InternalIterator> meta_iter;
meta_iter.reset(metaindex_block.NewDataIterator(
BytewiseComparator(), kDisableGlobalSequenceNumber));
return FindMetaBlock(meta_iter.get(), meta_block_name, block_handle);
}
Status ReadMetaBlock(RandomAccessFileReader* file,
FilePrefetchBuffer* prefetch_buffer, uint64_t file_size,
uint64_t table_magic_number,
const ImmutableCFOptions& ioptions,
const std::string& meta_block_name, BlockType block_type,
BlockContents* contents, bool /*compression_type_missing*/,
MemoryAllocator* memory_allocator) {
Status status;
Footer footer;
IOOptions opts;
status = ReadFooterFromFile(opts, file, prefetch_buffer, file_size, &footer,
table_magic_number);
if (!status.ok()) {
return status;
}
// Reading metaindex block
auto metaindex_handle = footer.metaindex_handle();
BlockContents metaindex_contents;
ReadOptions read_options;
read_options.verify_checksums = false;
PersistentCacheOptions cache_options;
BlockFetcher block_fetcher(
file, prefetch_buffer, footer, read_options, metaindex_handle,
&metaindex_contents, ioptions, false /* decompress */,
false /*maybe_compressed*/, BlockType::kMetaIndex,
UncompressionDict::GetEmptyDict(), cache_options, memory_allocator);
status = block_fetcher.ReadBlockContents();
if (!status.ok()) {
return status;
}
// meta block is never compressed. Need to add uncompress logic if we are to
// compress it.
// Finding metablock
Block metaindex_block(std::move(metaindex_contents));
std::unique_ptr<InternalIterator> meta_iter;
meta_iter.reset(metaindex_block.NewDataIterator(
BytewiseComparator(), kDisableGlobalSequenceNumber));
BlockHandle block_handle;
status = FindMetaBlock(meta_iter.get(), meta_block_name, &block_handle);
if (!status.ok()) {
return status;
}
// Reading metablock
BlockFetcher block_fetcher2(
file, prefetch_buffer, footer, read_options, block_handle, contents,
ioptions, false /* decompress */, false /*maybe_compressed*/, block_type,
UncompressionDict::GetEmptyDict(), cache_options, memory_allocator);
return block_fetcher2.ReadBlockContents();
}
} // namespace ROCKSDB_NAMESPACE