You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 
rocksdb/table/block_based/block_based_table_builder.cc

2093 lines
78 KiB

// 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).
//
// 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.
#include "table/block_based/block_based_table_builder.h"
#include <assert.h>
#include <stdio.h>
#include <atomic>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <string>
#include <unordered_map>
#include <utility>
#include "cache/cache_entry_roles.h"
#include "cache/cache_key.h"
#include "cache/cache_reservation_manager.h"
#include "db/dbformat.h"
#include "index_builder.h"
#include "logging/logging.h"
#include "memory/memory_allocator.h"
#include "rocksdb/cache.h"
#include "rocksdb/comparator.h"
#include "rocksdb/env.h"
#include "rocksdb/filter_policy.h"
#include "rocksdb/flush_block_policy.h"
#include "rocksdb/merge_operator.h"
#include "rocksdb/table.h"
#include "rocksdb/types.h"
#include "table/block_based/block.h"
#include "table/block_based/block_based_table_factory.h"
#include "table/block_based/block_based_table_reader.h"
#include "table/block_based/block_builder.h"
#include "table/block_based/block_like_traits.h"
#include "table/block_based/filter_block.h"
#include "table/block_based/filter_policy_internal.h"
#include "table/block_based/full_filter_block.h"
#include "table/block_based/partitioned_filter_block.h"
#include "table/format.h"
#include "table/meta_blocks.h"
#include "table/table_builder.h"
#include "util/coding.h"
#include "util/compression.h"
#include "util/stop_watch.h"
#include "util/string_util.h"
#include "util/work_queue.h"
namespace ROCKSDB_NAMESPACE {
extern const std::string kHashIndexPrefixesBlock;
extern const std::string kHashIndexPrefixesMetadataBlock;
// Without anonymous namespace here, we fail the warning -Wmissing-prototypes
namespace {
constexpr size_t kBlockTrailerSize = BlockBasedTable::kBlockTrailerSize;
// Create a filter block builder based on its type.
FilterBlockBuilder* CreateFilterBlockBuilder(
const ImmutableCFOptions& /*opt*/, const MutableCFOptions& mopt,
const FilterBuildingContext& context,
const bool use_delta_encoding_for_index_values,
PartitionedIndexBuilder* const p_index_builder) {
const BlockBasedTableOptions& table_opt = context.table_options;
assert(table_opt.filter_policy); // precondition
FilterBitsBuilder* filter_bits_builder =
BloomFilterPolicy::GetBuilderFromContext(context);
if (filter_bits_builder == nullptr) {
return nullptr;
} else {
if (table_opt.partition_filters) {
assert(p_index_builder != nullptr);
// Since after partition cut request from filter builder it takes time
// until index builder actully cuts the partition, until the end of a
// data block potentially with many keys, we take the lower bound as
// partition size.
assert(table_opt.block_size_deviation <= 100);
auto partition_size =
static_cast<uint32_t>(((table_opt.metadata_block_size *
(100 - table_opt.block_size_deviation)) +
99) /
100);
partition_size = std::max(partition_size, static_cast<uint32_t>(1));
return new PartitionedFilterBlockBuilder(
mopt.prefix_extractor.get(), table_opt.whole_key_filtering,
filter_bits_builder, table_opt.index_block_restart_interval,
use_delta_encoding_for_index_values, p_index_builder, partition_size);
} else {
return new FullFilterBlockBuilder(mopt.prefix_extractor.get(),
table_opt.whole_key_filtering,
filter_bits_builder);
}
}
}
bool GoodCompressionRatio(size_t compressed_size, size_t raw_size) {
// Check to see if compressed less than 12.5%
return compressed_size < raw_size - (raw_size / 8u);
}
} // namespace
// format_version is the block format as defined in include/rocksdb/table.h
Slice CompressBlock(const Slice& raw, const CompressionInfo& info,
CompressionType* type, uint32_t format_version,
bool do_sample, std::string* compressed_output,
std::string* sampled_output_fast,
std::string* sampled_output_slow) {
assert(type);
assert(compressed_output);
assert(compressed_output->empty());
// If requested, we sample one in every N block with a
// fast and slow compression algorithm and report the stats.
// The users can use these stats to decide if it is worthwhile
// enabling compression and they also get a hint about which
// compression algorithm wil be beneficial.
if (do_sample && info.SampleForCompression() &&
Random::GetTLSInstance()->OneIn(
static_cast<int>(info.SampleForCompression()))) {
// Sampling with a fast compression algorithm
if (sampled_output_fast && (LZ4_Supported() || Snappy_Supported())) {
CompressionType c =
LZ4_Supported() ? kLZ4Compression : kSnappyCompression;
CompressionContext context(c);
CompressionOptions options;
CompressionInfo info_tmp(options, context,
CompressionDict::GetEmptyDict(), c,
info.SampleForCompression());
CompressData(raw, info_tmp, GetCompressFormatForVersion(format_version),
sampled_output_fast);
}
// Sampling with a slow but high-compression algorithm
if (sampled_output_slow && (ZSTD_Supported() || Zlib_Supported())) {
CompressionType c = ZSTD_Supported() ? kZSTD : kZlibCompression;
CompressionContext context(c);
CompressionOptions options;
CompressionInfo info_tmp(options, context,
CompressionDict::GetEmptyDict(), c,
info.SampleForCompression());
CompressData(raw, info_tmp, GetCompressFormatForVersion(format_version),
sampled_output_slow);
}
}
if (info.type() == kNoCompression) {
*type = kNoCompression;
return raw;
}
// Actually compress the data; if the compression method is not supported,
// or the compression fails etc., just fall back to uncompressed
if (!CompressData(raw, info, GetCompressFormatForVersion(format_version),
compressed_output)) {
*type = kNoCompression;
return raw;
}
// Check the compression ratio; if it's not good enough, just fall back to
// uncompressed
if (!GoodCompressionRatio(compressed_output->size(), raw.size())) {
*type = kNoCompression;
return raw;
}
*type = info.type();
return *compressed_output;
}
// kBlockBasedTableMagicNumber was picked by running
// echo rocksdb.table.block_based | sha1sum
// and taking the leading 64 bits.
// Please note that kBlockBasedTableMagicNumber may also be accessed by other
// .cc files
// for that reason we declare it extern in the header but to get the space
// allocated
// it must be not extern in one place.
const uint64_t kBlockBasedTableMagicNumber = 0x88e241b785f4cff7ull;
// We also support reading and writing legacy block based table format (for
// backwards compatibility)
const uint64_t kLegacyBlockBasedTableMagicNumber = 0xdb4775248b80fb57ull;
// A collector that collects properties of interest to block-based table.
// For now this class looks heavy-weight since we only write one additional
// property.
// But in the foreseeable future, we will add more and more properties that are
// specific to block-based table.
class BlockBasedTableBuilder::BlockBasedTablePropertiesCollector
: public IntTblPropCollector {
public:
explicit BlockBasedTablePropertiesCollector(
BlockBasedTableOptions::IndexType index_type, bool whole_key_filtering,
bool prefix_filtering)
: index_type_(index_type),
whole_key_filtering_(whole_key_filtering),
prefix_filtering_(prefix_filtering) {}
Status InternalAdd(const Slice& /*key*/, const Slice& /*value*/,
uint64_t /*file_size*/) override {
// Intentionally left blank. Have no interest in collecting stats for
// individual key/value pairs.
return Status::OK();
}
virtual void BlockAdd(uint64_t /* block_raw_bytes */,
uint64_t /* block_compressed_bytes_fast */,
uint64_t /* block_compressed_bytes_slow */) override {
// Intentionally left blank. No interest in collecting stats for
// blocks.
return;
}
Status Finish(UserCollectedProperties* properties) override {
std::string val;
PutFixed32(&val, static_cast<uint32_t>(index_type_));
properties->insert({BlockBasedTablePropertyNames::kIndexType, val});
properties->insert({BlockBasedTablePropertyNames::kWholeKeyFiltering,
whole_key_filtering_ ? kPropTrue : kPropFalse});
properties->insert({BlockBasedTablePropertyNames::kPrefixFiltering,
prefix_filtering_ ? kPropTrue : kPropFalse});
return Status::OK();
}
// The name of the properties collector can be used for debugging purpose.
const char* Name() const override {
return "BlockBasedTablePropertiesCollector";
}
UserCollectedProperties GetReadableProperties() const override {
// Intentionally left blank.
return UserCollectedProperties();
}
private:
BlockBasedTableOptions::IndexType index_type_;
bool whole_key_filtering_;
bool prefix_filtering_;
};
struct BlockBasedTableBuilder::Rep {
const ImmutableOptions ioptions;
const MutableCFOptions moptions;
const BlockBasedTableOptions table_options;
const InternalKeyComparator& internal_comparator;
WritableFileWriter* file;
std::atomic<uint64_t> offset;
size_t alignment;
BlockBuilder data_block;
// Buffers uncompressed data blocks to replay later. Needed when
// compression dictionary is enabled so we can finalize the dictionary before
// compressing any data blocks.
std::vector<std::string> data_block_buffers;
BlockBuilder range_del_block;
InternalKeySliceTransform internal_prefix_transform;
std::unique_ptr<IndexBuilder> index_builder;
PartitionedIndexBuilder* p_index_builder_ = nullptr;
std::string last_key;
const Slice* first_key_in_next_block = nullptr;
CompressionType compression_type;
uint64_t sample_for_compression;
std::atomic<uint64_t> compressible_input_data_bytes;
std::atomic<uint64_t> uncompressible_input_data_bytes;
std::atomic<uint64_t> sampled_input_data_bytes;
std::atomic<uint64_t> sampled_output_slow_data_bytes;
std::atomic<uint64_t> sampled_output_fast_data_bytes;
CompressionOptions compression_opts;
std::unique_ptr<CompressionDict> compression_dict;
std::vector<std::unique_ptr<CompressionContext>> compression_ctxs;
std::vector<std::unique_ptr<UncompressionContext>> verify_ctxs;
std::unique_ptr<UncompressionDict> verify_dict;
size_t data_begin_offset = 0;
TableProperties props;
// States of the builder.
//
// - `kBuffered`: This is the initial state where zero or more data blocks are
// accumulated uncompressed in-memory. From this state, call
// `EnterUnbuffered()` to finalize the compression dictionary if enabled,
// compress/write out any buffered blocks, and proceed to the `kUnbuffered`
// state.
//
// - `kUnbuffered`: This is the state when compression dictionary is finalized
// either because it wasn't enabled in the first place or it's been created
// from sampling previously buffered data. In this state, blocks are simply
// compressed/written out as they fill up. From this state, call `Finish()`
// to complete the file (write meta-blocks, etc.), or `Abandon()` to delete
// the partially created file.
//
// - `kClosed`: This indicates either `Finish()` or `Abandon()` has been
// called, so the table builder is no longer usable. We must be in this
// state by the time the destructor runs.
enum class State {
kBuffered,
kUnbuffered,
kClosed,
};
State state;
// `kBuffered` state is allowed only as long as the buffering of uncompressed
// data blocks (see `data_block_buffers`) does not exceed `buffer_limit`.
uint64_t buffer_limit;
std::shared_ptr<CacheReservationManager>
compression_dict_buffer_cache_res_mgr;
const bool use_delta_encoding_for_index_values;
std::unique_ptr<FilterBlockBuilder> filter_builder;
OffsetableCacheKey base_cache_key;
const TableFileCreationReason reason;
BlockHandle pending_handle; // Handle to add to index block
std::string compressed_output;
std::unique_ptr<FlushBlockPolicy> flush_block_policy;
std::vector<std::unique_ptr<IntTblPropCollector>> table_properties_collectors;
std::unique_ptr<ParallelCompressionRep> pc_rep;
uint64_t get_offset() { return offset.load(std::memory_order_relaxed); }
void set_offset(uint64_t o) { offset.store(o, std::memory_order_relaxed); }
bool IsParallelCompressionEnabled() const {
return compression_opts.parallel_threads > 1;
}
Status GetStatus() {
// We need to make modifications of status visible when status_ok is set
// to false, and this is ensured by status_mutex, so no special memory
// order for status_ok is required.
if (status_ok.load(std::memory_order_relaxed)) {
return Status::OK();
} else {
return CopyStatus();
}
}
Status CopyStatus() {
std::lock_guard<std::mutex> lock(status_mutex);
return status;
}
IOStatus GetIOStatus() {
// We need to make modifications of io_status visible when status_ok is set
// to false, and this is ensured by io_status_mutex, so no special memory
// order for io_status_ok is required.
if (io_status_ok.load(std::memory_order_relaxed)) {
return IOStatus::OK();
} else {
return CopyIOStatus();
}
}
IOStatus CopyIOStatus() {
std::lock_guard<std::mutex> lock(io_status_mutex);
return io_status;
}
// Never erase an existing status that is not OK.
void SetStatus(Status s) {
if (!s.ok() && status_ok.load(std::memory_order_relaxed)) {
// Locking is an overkill for non compression_opts.parallel_threads
// case but since it's unlikely that s is not OK, we take this cost
// to be simplicity.
std::lock_guard<std::mutex> lock(status_mutex);
status = s;
status_ok.store(false, std::memory_order_relaxed);
}
}
// Never erase an existing I/O status that is not OK.
// Calling this will also SetStatus(ios)
void SetIOStatus(IOStatus ios) {
if (!ios.ok() && io_status_ok.load(std::memory_order_relaxed)) {
// Locking is an overkill for non compression_opts.parallel_threads
// case but since it's unlikely that s is not OK, we take this cost
// to be simplicity.
std::lock_guard<std::mutex> lock(io_status_mutex);
io_status = ios;
io_status_ok.store(false, std::memory_order_relaxed);
}
SetStatus(ios);
}
Rep(const BlockBasedTableOptions& table_opt, const TableBuilderOptions& tbo,
WritableFileWriter* f)
: ioptions(tbo.ioptions),
moptions(tbo.moptions),
table_options(table_opt),
internal_comparator(tbo.internal_comparator),
file(f),
offset(0),
alignment(table_options.block_align
? std::min(static_cast<size_t>(table_options.block_size),
kDefaultPageSize)
: 0),
data_block(table_options.block_restart_interval,
table_options.use_delta_encoding,
false /* use_value_delta_encoding */,
tbo.internal_comparator.user_comparator()
->CanKeysWithDifferentByteContentsBeEqual()
? BlockBasedTableOptions::kDataBlockBinarySearch
: table_options.data_block_index_type,
table_options.data_block_hash_table_util_ratio),
range_del_block(1 /* block_restart_interval */),
internal_prefix_transform(tbo.moptions.prefix_extractor.get()),
compression_type(tbo.compression_type),
sample_for_compression(tbo.moptions.sample_for_compression),
compressible_input_data_bytes(0),
uncompressible_input_data_bytes(0),
sampled_input_data_bytes(0),
sampled_output_slow_data_bytes(0),
sampled_output_fast_data_bytes(0),
compression_opts(tbo.compression_opts),
compression_dict(),
compression_ctxs(tbo.compression_opts.parallel_threads),
verify_ctxs(tbo.compression_opts.parallel_threads),
verify_dict(),
state((tbo.compression_opts.max_dict_bytes > 0) ? State::kBuffered
: State::kUnbuffered),
use_delta_encoding_for_index_values(table_opt.format_version >= 4 &&
!table_opt.block_align),
reason(tbo.reason),
flush_block_policy(
table_options.flush_block_policy_factory->NewFlushBlockPolicy(
table_options, data_block)),
status_ok(true),
io_status_ok(true) {
if (tbo.target_file_size == 0) {
buffer_limit = compression_opts.max_dict_buffer_bytes;
} else if (compression_opts.max_dict_buffer_bytes == 0) {
buffer_limit = tbo.target_file_size;
} else {
buffer_limit = std::min(tbo.target_file_size,
compression_opts.max_dict_buffer_bytes);
}
const auto compress_dict_build_buffer_charged =
table_options.cache_usage_options.options_overrides
.at(CacheEntryRole::kCompressionDictionaryBuildingBuffer)
.charged;
if (table_options.block_cache &&
(compress_dict_build_buffer_charged ==
CacheEntryRoleOptions::Decision::kEnabled ||
compress_dict_build_buffer_charged ==
CacheEntryRoleOptions::Decision::kFallback)) {
compression_dict_buffer_cache_res_mgr =
std::make_shared<CacheReservationManagerImpl<
CacheEntryRole::kCompressionDictionaryBuildingBuffer>>(
table_options.block_cache);
} else {
compression_dict_buffer_cache_res_mgr = nullptr;
}
for (uint32_t i = 0; i < compression_opts.parallel_threads; i++) {
compression_ctxs[i].reset(new CompressionContext(compression_type));
}
if (table_options.index_type ==
BlockBasedTableOptions::kTwoLevelIndexSearch) {
p_index_builder_ = PartitionedIndexBuilder::CreateIndexBuilder(
&internal_comparator, use_delta_encoding_for_index_values,
table_options);
index_builder.reset(p_index_builder_);
} else {
index_builder.reset(IndexBuilder::CreateIndexBuilder(
table_options.index_type, &internal_comparator,
&this->internal_prefix_transform, use_delta_encoding_for_index_values,
table_options));
}
if (ioptions.optimize_filters_for_hits && tbo.is_bottommost) {
// Apply optimize_filters_for_hits setting here when applicable by
// skipping filter generation
filter_builder.reset();
} else if (tbo.skip_filters) {
// For SstFileWriter skip_filters
filter_builder.reset();
} else if (!table_options.filter_policy) {
// Null filter_policy -> no filter
filter_builder.reset();
} else {
FilterBuildingContext filter_context(table_options);
filter_context.info_log = ioptions.logger;
filter_context.column_family_name = tbo.column_family_name;
filter_context.reason = reason;
// Only populate other fields if known to be in LSM rather than
// generating external SST file
if (reason != TableFileCreationReason::kMisc) {
filter_context.compaction_style = ioptions.compaction_style;
filter_context.num_levels = ioptions.num_levels;
filter_context.level_at_creation = tbo.level_at_creation;
filter_context.is_bottommost = tbo.is_bottommost;
assert(filter_context.level_at_creation < filter_context.num_levels);
}
filter_builder.reset(CreateFilterBlockBuilder(
ioptions, moptions, filter_context,
use_delta_encoding_for_index_values, p_index_builder_));
}
assert(tbo.int_tbl_prop_collector_factories);
for (auto& factory : *tbo.int_tbl_prop_collector_factories) {
assert(factory);
table_properties_collectors.emplace_back(
factory->CreateIntTblPropCollector(tbo.column_family_id,
tbo.level_at_creation));
}
table_properties_collectors.emplace_back(
new BlockBasedTablePropertiesCollector(
table_options.index_type, table_options.whole_key_filtering,
moptions.prefix_extractor != nullptr));
const Comparator* ucmp = tbo.internal_comparator.user_comparator();
assert(ucmp);
if (ucmp->timestamp_size() > 0) {
table_properties_collectors.emplace_back(
new TimestampTablePropertiesCollector(ucmp));
}
if (table_options.verify_compression) {
for (uint32_t i = 0; i < compression_opts.parallel_threads; i++) {
verify_ctxs[i].reset(new UncompressionContext(compression_type));
}
}
// These are only needed for populating table properties
props.column_family_id = tbo.column_family_id;
props.column_family_name = tbo.column_family_name;
props.oldest_key_time = tbo.oldest_key_time;
props.file_creation_time = tbo.file_creation_time;
props.orig_file_number = tbo.cur_file_num;
props.db_id = tbo.db_id;
props.db_session_id = tbo.db_session_id;
props.db_host_id = ioptions.db_host_id;
if (!ReifyDbHostIdProperty(ioptions.env, &props.db_host_id).ok()) {
ROCKS_LOG_INFO(ioptions.logger, "db_host_id property will not be set");
}
}
Rep(const Rep&) = delete;
Rep& operator=(const Rep&) = delete;
private:
// Synchronize status & io_status accesses across threads from main thread,
// compression thread and write thread in parallel compression.
std::mutex status_mutex;
std::atomic<bool> status_ok;
Status status;
std::mutex io_status_mutex;
std::atomic<bool> io_status_ok;
IOStatus io_status;
};
struct BlockBasedTableBuilder::ParallelCompressionRep {
// Keys is a wrapper of vector of strings avoiding
// releasing string memories during vector clear()
// in order to save memory allocation overhead
class Keys {
public:
Keys() : keys_(kKeysInitSize), size_(0) {}
void PushBack(const Slice& key) {
if (size_ == keys_.size()) {
keys_.emplace_back(key.data(), key.size());
} else {
keys_[size_].assign(key.data(), key.size());
}
size_++;
}
void SwapAssign(std::vector<std::string>& keys) {
size_ = keys.size();
std::swap(keys_, keys);
}
void Clear() { size_ = 0; }
size_t Size() { return size_; }
std::string& Back() { return keys_[size_ - 1]; }
std::string& operator[](size_t idx) {
assert(idx < size_);
return keys_[idx];
}
private:
const size_t kKeysInitSize = 32;
std::vector<std::string> keys_;
size_t size_;
};
std::unique_ptr<Keys> curr_block_keys;
class BlockRepSlot;
// BlockRep instances are fetched from and recycled to
// block_rep_pool during parallel compression.
struct BlockRep {
Slice contents;
Slice compressed_contents;
std::unique_ptr<std::string> data;
std::unique_ptr<std::string> compressed_data;
CompressionType compression_type;
std::unique_ptr<std::string> first_key_in_next_block;
std::unique_ptr<Keys> keys;
std::unique_ptr<BlockRepSlot> slot;
Status status;
};
// Use a vector of BlockRep as a buffer for a determined number
// of BlockRep structures. All data referenced by pointers in
// BlockRep will be freed when this vector is destructed.
using BlockRepBuffer = std::vector<BlockRep>;
BlockRepBuffer block_rep_buf;
// Use a thread-safe queue for concurrent access from block
// building thread and writer thread.
using BlockRepPool = WorkQueue<BlockRep*>;
BlockRepPool block_rep_pool;
// Use BlockRepSlot to keep block order in write thread.
// slot_ will pass references to BlockRep
class BlockRepSlot {
public:
BlockRepSlot() : slot_(1) {}
template <typename T>
void Fill(T&& rep) {
slot_.push(std::forward<T>(rep));
};
void Take(BlockRep*& rep) { slot_.pop(rep); }
private:
// slot_ will pass references to BlockRep in block_rep_buf,
// and those references are always valid before the destruction of
// block_rep_buf.
WorkQueue<BlockRep*> slot_;
};
// Compression queue will pass references to BlockRep in block_rep_buf,
// and those references are always valid before the destruction of
// block_rep_buf.
using CompressQueue = WorkQueue<BlockRep*>;
CompressQueue compress_queue;
std::vector<port::Thread> compress_thread_pool;
// Write queue will pass references to BlockRep::slot in block_rep_buf,
// and those references are always valid before the corresponding
// BlockRep::slot is destructed, which is before the destruction of
// block_rep_buf.
using WriteQueue = WorkQueue<BlockRepSlot*>;
WriteQueue write_queue;
std::unique_ptr<port::Thread> write_thread;
// Estimate output file size when parallel compression is enabled. This is
// necessary because compression & flush are no longer synchronized,
// and BlockBasedTableBuilder::FileSize() is no longer accurate.
// memory_order_relaxed suffices because accurate statistics is not required.
class FileSizeEstimator {
public:
explicit FileSizeEstimator()
: raw_bytes_compressed(0),
raw_bytes_curr_block(0),
raw_bytes_curr_block_set(false),
raw_bytes_inflight(0),
blocks_inflight(0),
curr_compression_ratio(0),
estimated_file_size(0) {}
// Estimate file size when a block is about to be emitted to
// compression thread
void EmitBlock(uint64_t raw_block_size, uint64_t curr_file_size) {
uint64_t new_raw_bytes_inflight =
raw_bytes_inflight.fetch_add(raw_block_size,
std::memory_order_relaxed) +
raw_block_size;
uint64_t new_blocks_inflight =
blocks_inflight.fetch_add(1, std::memory_order_relaxed) + 1;
estimated_file_size.store(
curr_file_size +
static_cast<uint64_t>(
static_cast<double>(new_raw_bytes_inflight) *
curr_compression_ratio.load(std::memory_order_relaxed)) +
new_blocks_inflight * kBlockTrailerSize,
std::memory_order_relaxed);
}
// Estimate file size when a block is already reaped from
// compression thread
void ReapBlock(uint64_t compressed_block_size, uint64_t curr_file_size) {
assert(raw_bytes_curr_block_set);
uint64_t new_raw_bytes_compressed =
raw_bytes_compressed + raw_bytes_curr_block;
assert(new_raw_bytes_compressed > 0);
curr_compression_ratio.store(
(curr_compression_ratio.load(std::memory_order_relaxed) *
raw_bytes_compressed +
compressed_block_size) /
static_cast<double>(new_raw_bytes_compressed),
std::memory_order_relaxed);
raw_bytes_compressed = new_raw_bytes_compressed;
uint64_t new_raw_bytes_inflight =
raw_bytes_inflight.fetch_sub(raw_bytes_curr_block,
std::memory_order_relaxed) -
raw_bytes_curr_block;
uint64_t new_blocks_inflight =
blocks_inflight.fetch_sub(1, std::memory_order_relaxed) - 1;
estimated_file_size.store(
curr_file_size +
static_cast<uint64_t>(
static_cast<double>(new_raw_bytes_inflight) *
curr_compression_ratio.load(std::memory_order_relaxed)) +
new_blocks_inflight * kBlockTrailerSize,
std::memory_order_relaxed);
raw_bytes_curr_block_set = false;
}
void SetEstimatedFileSize(uint64_t size) {
estimated_file_size.store(size, std::memory_order_relaxed);
}
uint64_t GetEstimatedFileSize() {
return estimated_file_size.load(std::memory_order_relaxed);
}
void SetCurrBlockRawSize(uint64_t size) {
raw_bytes_curr_block = size;
raw_bytes_curr_block_set = true;
}
private:
// Raw bytes compressed so far.
uint64_t raw_bytes_compressed;
// Size of current block being appended.
uint64_t raw_bytes_curr_block;
// Whether raw_bytes_curr_block has been set for next
// ReapBlock call.
bool raw_bytes_curr_block_set;
// Raw bytes under compression and not appended yet.
std::atomic<uint64_t> raw_bytes_inflight;
// Number of blocks under compression and not appended yet.
std::atomic<uint64_t> blocks_inflight;
// Current compression ratio, maintained by BGWorkWriteRawBlock.
std::atomic<double> curr_compression_ratio;
// Estimated SST file size.
std::atomic<uint64_t> estimated_file_size;
};
FileSizeEstimator file_size_estimator;
// Facilities used for waiting first block completion. Need to Wait for
// the completion of first block compression and flush to get a non-zero
// compression ratio.
std::atomic<bool> first_block_processed;
std::condition_variable first_block_cond;
std::mutex first_block_mutex;
explicit ParallelCompressionRep(uint32_t parallel_threads)
: curr_block_keys(new Keys()),
block_rep_buf(parallel_threads),
block_rep_pool(parallel_threads),
compress_queue(parallel_threads),
write_queue(parallel_threads),
first_block_processed(false) {
for (uint32_t i = 0; i < parallel_threads; i++) {
block_rep_buf[i].contents = Slice();
block_rep_buf[i].compressed_contents = Slice();
block_rep_buf[i].data.reset(new std::string());
block_rep_buf[i].compressed_data.reset(new std::string());
block_rep_buf[i].compression_type = CompressionType();
block_rep_buf[i].first_key_in_next_block.reset(new std::string());
block_rep_buf[i].keys.reset(new Keys());
block_rep_buf[i].slot.reset(new BlockRepSlot());
block_rep_buf[i].status = Status::OK();
block_rep_pool.push(&block_rep_buf[i]);
}
}
~ParallelCompressionRep() { block_rep_pool.finish(); }
// Make a block prepared to be emitted to compression thread
// Used in non-buffered mode
BlockRep* PrepareBlock(CompressionType compression_type,
const Slice* first_key_in_next_block,
BlockBuilder* data_block) {
BlockRep* block_rep =
PrepareBlockInternal(compression_type, first_key_in_next_block);
assert(block_rep != nullptr);
data_block->SwapAndReset(*(block_rep->data));
block_rep->contents = *(block_rep->data);
std::swap(block_rep->keys, curr_block_keys);
curr_block_keys->Clear();
return block_rep;
}
// Used in EnterUnbuffered
BlockRep* PrepareBlock(CompressionType compression_type,
const Slice* first_key_in_next_block,
std::string* data_block,
std::vector<std::string>* keys) {
BlockRep* block_rep =
PrepareBlockInternal(compression_type, first_key_in_next_block);
assert(block_rep != nullptr);
std::swap(*(block_rep->data), *data_block);
block_rep->contents = *(block_rep->data);
block_rep->keys->SwapAssign(*keys);
return block_rep;
}
// Emit a block to compression thread
void EmitBlock(BlockRep* block_rep) {
assert(block_rep != nullptr);
assert(block_rep->status.ok());
if (!write_queue.push(block_rep->slot.get())) {
return;
}
if (!compress_queue.push(block_rep)) {
return;
}
if (!first_block_processed.load(std::memory_order_relaxed)) {
std::unique_lock<std::mutex> lock(first_block_mutex);
first_block_cond.wait(lock, [this] {
return first_block_processed.load(std::memory_order_relaxed);
});
}
}
// Reap a block from compression thread
void ReapBlock(BlockRep* block_rep) {
assert(block_rep != nullptr);
block_rep->compressed_data->clear();
block_rep_pool.push(block_rep);
if (!first_block_processed.load(std::memory_order_relaxed)) {
std::lock_guard<std::mutex> lock(first_block_mutex);
first_block_processed.store(true, std::memory_order_relaxed);
first_block_cond.notify_one();
}
}
private:
BlockRep* PrepareBlockInternal(CompressionType compression_type,
const Slice* first_key_in_next_block) {
BlockRep* block_rep = nullptr;
block_rep_pool.pop(block_rep);
assert(block_rep != nullptr);
assert(block_rep->data);
block_rep->compression_type = compression_type;
if (first_key_in_next_block == nullptr) {
block_rep->first_key_in_next_block.reset(nullptr);
} else {
block_rep->first_key_in_next_block->assign(
first_key_in_next_block->data(), first_key_in_next_block->size());
}
return block_rep;
}
};
BlockBasedTableBuilder::BlockBasedTableBuilder(
const BlockBasedTableOptions& table_options, const TableBuilderOptions& tbo,
WritableFileWriter* file) {
BlockBasedTableOptions sanitized_table_options(table_options);
if (sanitized_table_options.format_version == 0 &&
sanitized_table_options.checksum != kCRC32c) {
ROCKS_LOG_WARN(
tbo.ioptions.logger,
"Silently converting format_version to 1 because checksum is "
"non-default");
// silently convert format_version to 1 to keep consistent with current
// behavior
sanitized_table_options.format_version = 1;
}
rep_ = new Rep(sanitized_table_options, tbo, file);
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::BlockBasedTableBuilder:PreSetupBaseCacheKey",
const_cast<TableProperties*>(&rep_->props));
BlockBasedTable::SetupBaseCacheKey(&rep_->props, tbo.db_session_id,
tbo.cur_file_num, &rep_->base_cache_key);
if (rep_->IsParallelCompressionEnabled()) {
StartParallelCompression();
}
}
BlockBasedTableBuilder::~BlockBasedTableBuilder() {
// Catch errors where caller forgot to call Finish()
assert(rep_->state == Rep::State::kClosed);
delete rep_;
}
void BlockBasedTableBuilder::Add(const Slice& key, const Slice& value) {
Rep* r = rep_;
assert(rep_->state != Rep::State::kClosed);
if (!ok()) return;
ValueType value_type = ExtractValueType(key);
if (IsValueType(value_type)) {
#ifndef NDEBUG
if (r->props.num_entries > r->props.num_range_deletions) {
assert(r->internal_comparator.Compare(key, Slice(r->last_key)) > 0);
}
#endif // !NDEBUG
auto should_flush = r->flush_block_policy->Update(key, value);
if (should_flush) {
assert(!r->data_block.empty());
r->first_key_in_next_block = &key;
Flush();
if (r->state == Rep::State::kBuffered) {
bool exceeds_buffer_limit =
(r->buffer_limit != 0 && r->data_begin_offset > r->buffer_limit);
bool exceeds_global_block_cache_limit = false;
// Increase cache charging for the last buffered data block
// only if the block is not going to be unbuffered immediately
// and there exists a cache reservation manager
if (!exceeds_buffer_limit &&
r->compression_dict_buffer_cache_res_mgr != nullptr) {
Status s =
r->compression_dict_buffer_cache_res_mgr->UpdateCacheReservation(
r->data_begin_offset);
exceeds_global_block_cache_limit = s.IsMemoryLimit();
}
if (exceeds_buffer_limit || exceeds_global_block_cache_limit) {
EnterUnbuffered();
}
}
// Add item to index block.
// We do not emit the index entry for a block until we have seen the
// first key for the next data block. This allows us to use shorter
// keys in the index block. For example, consider a block boundary
// between the keys "the quick brown fox" and "the who". We can use
// "the r" as the key for the index block entry since it is >= all
// entries in the first block and < all entries in subsequent
// blocks.
if (ok() && r->state == Rep::State::kUnbuffered) {
if (r->IsParallelCompressionEnabled()) {
r->pc_rep->curr_block_keys->Clear();
} else {
r->index_builder->AddIndexEntry(&r->last_key, &key,
r->pending_handle);
}
}
}
// Note: PartitionedFilterBlockBuilder requires key being added to filter
// builder after being added to index builder.
if (r->state == Rep::State::kUnbuffered) {
if (r->IsParallelCompressionEnabled()) {
r->pc_rep->curr_block_keys->PushBack(key);
} else {
if (r->filter_builder != nullptr) {
size_t ts_sz =
r->internal_comparator.user_comparator()->timestamp_size();
r->filter_builder->Add(ExtractUserKeyAndStripTimestamp(key, ts_sz));
}
}
}
r->data_block.AddWithLastKey(key, value, r->last_key);
r->last_key.assign(key.data(), key.size());
if (r->state == Rep::State::kBuffered) {
// Buffered keys will be replayed from data_block_buffers during
// `Finish()` once compression dictionary has been finalized.
} else {
if (!r->IsParallelCompressionEnabled()) {
r->index_builder->OnKeyAdded(key);
}
}
// TODO offset passed in is not accurate for parallel compression case
NotifyCollectTableCollectorsOnAdd(key, value, r->get_offset(),
r->table_properties_collectors,
r->ioptions.logger);
} else if (value_type == kTypeRangeDeletion) {
r->range_del_block.Add(key, value);
// TODO offset passed in is not accurate for parallel compression case
NotifyCollectTableCollectorsOnAdd(key, value, r->get_offset(),
r->table_properties_collectors,
r->ioptions.logger);
} else {
assert(false);
}
r->props.num_entries++;
r->props.raw_key_size += key.size();
r->props.raw_value_size += value.size();
if (value_type == kTypeDeletion || value_type == kTypeSingleDeletion) {
r->props.num_deletions++;
} else if (value_type == kTypeRangeDeletion) {
r->props.num_deletions++;
r->props.num_range_deletions++;
} else if (value_type == kTypeMerge) {
r->props.num_merge_operands++;
}
}
void BlockBasedTableBuilder::Flush() {
Rep* r = rep_;
assert(rep_->state != Rep::State::kClosed);
if (!ok()) return;
if (r->data_block.empty()) return;
if (r->IsParallelCompressionEnabled() &&
r->state == Rep::State::kUnbuffered) {
r->data_block.Finish();
ParallelCompressionRep::BlockRep* block_rep = r->pc_rep->PrepareBlock(
r->compression_type, r->first_key_in_next_block, &(r->data_block));
assert(block_rep != nullptr);
r->pc_rep->file_size_estimator.EmitBlock(block_rep->data->size(),
r->get_offset());
r->pc_rep->EmitBlock(block_rep);
} else {
WriteBlock(&r->data_block, &r->pending_handle, BlockType::kData);
}
}
void BlockBasedTableBuilder::WriteBlock(BlockBuilder* block,
BlockHandle* handle,
BlockType block_type) {
block->Finish();
std::string raw_block_contents;
raw_block_contents.reserve(rep_->table_options.block_size);
block->SwapAndReset(raw_block_contents);
if (rep_->state == Rep::State::kBuffered) {
assert(block_type == BlockType::kData);
rep_->data_block_buffers.emplace_back(std::move(raw_block_contents));
rep_->data_begin_offset += rep_->data_block_buffers.back().size();
return;
}
WriteBlock(raw_block_contents, handle, block_type);
}
void BlockBasedTableBuilder::WriteBlock(const Slice& raw_block_contents,
BlockHandle* handle,
BlockType block_type) {
Rep* r = rep_;
assert(r->state == Rep::State::kUnbuffered);
Slice block_contents;
CompressionType type;
Status compress_status;
bool is_data_block = block_type == BlockType::kData;
CompressAndVerifyBlock(raw_block_contents, is_data_block,
*(r->compression_ctxs[0]), r->verify_ctxs[0].get(),
&(r->compressed_output), &(block_contents), &type,
&compress_status);
r->SetStatus(compress_status);
if (!ok()) {
return;
}
WriteRawBlock(block_contents, type, handle, block_type, &raw_block_contents);
r->compressed_output.clear();
if (is_data_block) {
r->props.data_size = r->get_offset();
++r->props.num_data_blocks;
}
}
void BlockBasedTableBuilder::BGWorkCompression(
const CompressionContext& compression_ctx,
UncompressionContext* verify_ctx) {
ParallelCompressionRep::BlockRep* block_rep = nullptr;
while (rep_->pc_rep->compress_queue.pop(block_rep)) {
assert(block_rep != nullptr);
CompressAndVerifyBlock(block_rep->contents, true, /* is_data_block*/
compression_ctx, verify_ctx,
block_rep->compressed_data.get(),
&block_rep->compressed_contents,
&(block_rep->compression_type), &block_rep->status);
block_rep->slot->Fill(block_rep);
}
}
void BlockBasedTableBuilder::CompressAndVerifyBlock(
const Slice& raw_block_contents, bool is_data_block,
const CompressionContext& compression_ctx, UncompressionContext* verify_ctx,
std::string* compressed_output, Slice* block_contents,
CompressionType* type, Status* out_status) {
// File format contains a sequence of blocks where each block has:
// block_data: uint8[n]
// type: uint8
// crc: uint32
Rep* r = rep_;
bool is_status_ok = ok();
if (!r->IsParallelCompressionEnabled()) {
assert(is_status_ok);
}
*type = r->compression_type;
uint64_t sample_for_compression = r->sample_for_compression;
bool abort_compression = false;
StopWatchNano timer(
r->ioptions.clock,
ShouldReportDetailedTime(r->ioptions.env, r->ioptions.stats));
if (is_status_ok && raw_block_contents.size() < kCompressionSizeLimit) {
if (is_data_block) {
r->compressible_input_data_bytes.fetch_add(raw_block_contents.size(),
std::memory_order_relaxed);
}
const CompressionDict* compression_dict;
if (!is_data_block || r->compression_dict == nullptr) {
compression_dict = &CompressionDict::GetEmptyDict();
} else {
compression_dict = r->compression_dict.get();
}
assert(compression_dict != nullptr);
CompressionInfo compression_info(r->compression_opts, compression_ctx,
*compression_dict, *type,
sample_for_compression);
std::string sampled_output_fast;
std::string sampled_output_slow;
*block_contents = CompressBlock(
raw_block_contents, compression_info, type,
r->table_options.format_version, is_data_block /* do_sample */,
compressed_output, &sampled_output_fast, &sampled_output_slow);
if (sampled_output_slow.size() > 0 || sampled_output_fast.size() > 0) {
// Currently compression sampling is only enabled for data block.
assert(is_data_block);
r->sampled_input_data_bytes.fetch_add(raw_block_contents.size(),
std::memory_order_relaxed);
r->sampled_output_slow_data_bytes.fetch_add(sampled_output_slow.size(),
std::memory_order_relaxed);
r->sampled_output_fast_data_bytes.fetch_add(sampled_output_fast.size(),
std::memory_order_relaxed);
}
// notify collectors on block add
NotifyCollectTableCollectorsOnBlockAdd(
r->table_properties_collectors, raw_block_contents.size(),
sampled_output_fast.size(), sampled_output_slow.size());
// Some of the compression algorithms are known to be unreliable. If
// the verify_compression flag is set then try to de-compress the
// compressed data and compare to the input.
if (*type != kNoCompression && r->table_options.verify_compression) {
// Retrieve the uncompressed contents into a new buffer
const UncompressionDict* verify_dict;
if (!is_data_block || r->verify_dict == nullptr) {
verify_dict = &UncompressionDict::GetEmptyDict();
} else {
verify_dict = r->verify_dict.get();
}
assert(verify_dict != nullptr);
BlockContents contents;
UncompressionInfo uncompression_info(*verify_ctx, *verify_dict,
r->compression_type);
Status stat = UncompressBlockContentsForCompressionType(
uncompression_info, block_contents->data(), block_contents->size(),
&contents, r->table_options.format_version, r->ioptions);
if (stat.ok()) {
bool compressed_ok = contents.data.compare(raw_block_contents) == 0;
if (!compressed_ok) {
// The result of the compression was invalid. abort.
abort_compression = true;
ROCKS_LOG_ERROR(r->ioptions.logger,
"Decompressed block did not match raw block");
*out_status =
Status::Corruption("Decompressed block did not match raw block");
}
} else {
// Decompression reported an error. abort.
*out_status = Status::Corruption(std::string("Could not decompress: ") +
stat.getState());
abort_compression = true;
}
}
} else {
// Block is too big to be compressed.
if (is_data_block) {
r->uncompressible_input_data_bytes.fetch_add(raw_block_contents.size(),
std::memory_order_relaxed);
}
abort_compression = true;
}
if (is_data_block) {
r->uncompressible_input_data_bytes.fetch_add(kBlockTrailerSize,
std::memory_order_relaxed);
}
// Abort compression if the block is too big, or did not pass
// verification.
if (abort_compression) {
RecordTick(r->ioptions.stats, NUMBER_BLOCK_NOT_COMPRESSED);
*type = kNoCompression;
*block_contents = raw_block_contents;
} else if (*type != kNoCompression) {
if (ShouldReportDetailedTime(r->ioptions.env, r->ioptions.stats)) {
RecordTimeToHistogram(r->ioptions.stats, COMPRESSION_TIMES_NANOS,
timer.ElapsedNanos());
}
RecordInHistogram(r->ioptions.stats, BYTES_COMPRESSED,
raw_block_contents.size());
RecordTick(r->ioptions.stats, NUMBER_BLOCK_COMPRESSED);
} else if (*type != r->compression_type) {
RecordTick(r->ioptions.stats, NUMBER_BLOCK_NOT_COMPRESSED);
}
}
void BlockBasedTableBuilder::WriteRawBlock(const Slice& block_contents,
CompressionType type,
BlockHandle* handle,
BlockType block_type,
const Slice* raw_block_contents) {
Rep* r = rep_;
bool is_data_block = block_type == BlockType::kData;
StopWatch sw(r->ioptions.clock, r->ioptions.stats, WRITE_RAW_BLOCK_MICROS);
handle->set_offset(r->get_offset());
handle->set_size(block_contents.size());
assert(status().ok());
assert(io_status().ok());
{
IOStatus io_s = r->file->Append(block_contents);
if (!io_s.ok()) {
r->SetIOStatus(io_s);
return;
}
}
std::array<char, kBlockTrailerSize> trailer;
trailer[0] = type;
uint32_t checksum = ComputeBuiltinChecksumWithLastByte(
r->table_options.checksum, block_contents.data(), block_contents.size(),
/*last_byte*/ type);
if (block_type == BlockType::kFilter) {
Status s = r->filter_builder->MaybePostVerifyFilter(block_contents);
if (!s.ok()) {
r->SetStatus(s);
return;
}
}
EncodeFixed32(trailer.data() + 1, checksum);
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::WriteRawBlock:TamperWithChecksum",
trailer.data());
{
IOStatus io_s = r->file->Append(Slice(trailer.data(), trailer.size()));
if (!io_s.ok()) {
r->SetIOStatus(io_s);
return;
}
}
{
Status s = Status::OK();
bool warm_cache;
switch (r->table_options.prepopulate_block_cache) {
case BlockBasedTableOptions::PrepopulateBlockCache::kFlushOnly:
warm_cache = (r->reason == TableFileCreationReason::kFlush);
break;
case BlockBasedTableOptions::PrepopulateBlockCache::kDisable:
warm_cache = false;
break;
default:
// missing case
assert(false);
warm_cache = false;
}
if (warm_cache) {
if (type == kNoCompression) {
s = InsertBlockInCacheHelper(block_contents, handle, block_type);
} else if (raw_block_contents != nullptr) {
s = InsertBlockInCacheHelper(*raw_block_contents, handle, block_type);
}
if (!s.ok()) {
r->SetStatus(s);
return;
}
}
s = InsertBlockInCompressedCache(block_contents, type, handle);
if (!s.ok()) {
r->SetStatus(s);
return;
}
}
r->set_offset(r->get_offset() + block_contents.size() + kBlockTrailerSize);
if (r->table_options.block_align && is_data_block) {
size_t pad_bytes =
(r->alignment -
((block_contents.size() + kBlockTrailerSize) & (r->alignment - 1))) &
(r->alignment - 1);
IOStatus io_s = r->file->Pad(pad_bytes);
if (io_s.ok()) {
r->set_offset(r->get_offset() + pad_bytes);
} else {
r->SetIOStatus(io_s);
return;
}
}
if (r->IsParallelCompressionEnabled()) {
if (is_data_block) {
r->pc_rep->file_size_estimator.ReapBlock(block_contents.size(),
r->get_offset());
} else {
r->pc_rep->file_size_estimator.SetEstimatedFileSize(r->get_offset());
}
}
}
void BlockBasedTableBuilder::BGWorkWriteRawBlock() {
Rep* r = rep_;
ParallelCompressionRep::BlockRepSlot* slot = nullptr;
ParallelCompressionRep::BlockRep* block_rep = nullptr;
while (r->pc_rep->write_queue.pop(slot)) {
assert(slot != nullptr);
slot->Take(block_rep);
assert(block_rep != nullptr);
if (!block_rep->status.ok()) {
r->SetStatus(block_rep->status);
// Reap block so that blocked Flush() can finish
// if there is one, and Flush() will notice !ok() next time.
block_rep->status = Status::OK();
r->pc_rep->ReapBlock(block_rep);
continue;
}
for (size_t i = 0; i < block_rep->keys->Size(); i++) {
auto& key = (*block_rep->keys)[i];
if (r->filter_builder != nullptr) {
size_t ts_sz =
r->internal_comparator.user_comparator()->timestamp_size();
r->filter_builder->Add(ExtractUserKeyAndStripTimestamp(key, ts_sz));
}
r->index_builder->OnKeyAdded(key);
}
r->pc_rep->file_size_estimator.SetCurrBlockRawSize(block_rep->data->size());
WriteRawBlock(block_rep->compressed_contents, block_rep->compression_type,
&r->pending_handle, BlockType::kData, &block_rep->contents);
if (!ok()) {
break;
}
r->props.data_size = r->get_offset();
++r->props.num_data_blocks;
if (block_rep->first_key_in_next_block == nullptr) {
r->index_builder->AddIndexEntry(&(block_rep->keys->Back()), nullptr,
r->pending_handle);
} else {
Slice first_key_in_next_block =
Slice(*block_rep->first_key_in_next_block);
r->index_builder->AddIndexEntry(&(block_rep->keys->Back()),
&first_key_in_next_block,
r->pending_handle);
}
r->pc_rep->ReapBlock(block_rep);
}
}
void BlockBasedTableBuilder::StartParallelCompression() {
rep_->pc_rep.reset(
new ParallelCompressionRep(rep_->compression_opts.parallel_threads));
rep_->pc_rep->compress_thread_pool.reserve(
rep_->compression_opts.parallel_threads);
for (uint32_t i = 0; i < rep_->compression_opts.parallel_threads; i++) {
rep_->pc_rep->compress_thread_pool.emplace_back([this, i] {
BGWorkCompression(*(rep_->compression_ctxs[i]),
rep_->verify_ctxs[i].get());
});
}
rep_->pc_rep->write_thread.reset(
new port::Thread([this] { BGWorkWriteRawBlock(); }));
}
void BlockBasedTableBuilder::StopParallelCompression() {
rep_->pc_rep->compress_queue.finish();
for (auto& thread : rep_->pc_rep->compress_thread_pool) {
thread.join();
}
rep_->pc_rep->write_queue.finish();
rep_->pc_rep->write_thread->join();
}
Status BlockBasedTableBuilder::status() const { return rep_->GetStatus(); }
IOStatus BlockBasedTableBuilder::io_status() const {
return rep_->GetIOStatus();
}
namespace {
// Delete the entry resided in the cache.
template <class Entry>
void DeleteEntryCached(const Slice& /*key*/, void* value) {
auto entry = reinterpret_cast<Entry*>(value);
delete entry;
}
} // namespace
//
// Make a copy of the block contents and insert into compressed block cache
//
Status BlockBasedTableBuilder::InsertBlockInCompressedCache(
const Slice& block_contents, const CompressionType type,
const BlockHandle* handle) {
Rep* r = rep_;
Cache* block_cache_compressed = r->table_options.block_cache_compressed.get();
Status s;
if (type != kNoCompression && block_cache_compressed != nullptr) {
size_t size = block_contents.size();
auto ubuf =
AllocateBlock(size + 1, block_cache_compressed->memory_allocator());
memcpy(ubuf.get(), block_contents.data(), size);
ubuf[size] = type;
BlockContents* block_contents_to_cache =
new BlockContents(std::move(ubuf), size);
#ifndef NDEBUG
block_contents_to_cache->is_raw_block = true;
#endif // NDEBUG
CacheKey key = BlockBasedTable::GetCacheKey(rep_->base_cache_key, *handle);
s = block_cache_compressed->Insert(
key.AsSlice(), block_contents_to_cache,
block_contents_to_cache->ApproximateMemoryUsage(),
&DeleteEntryCached<BlockContents>);
if (s.ok()) {
RecordTick(rep_->ioptions.stats, BLOCK_CACHE_COMPRESSED_ADD);
} else {
RecordTick(rep_->ioptions.stats, BLOCK_CACHE_COMPRESSED_ADD_FAILURES);
}
// Invalidate OS cache.
r->file->InvalidateCache(static_cast<size_t>(r->get_offset()), size)
.PermitUncheckedError();
}
return s;
}
Status BlockBasedTableBuilder::InsertBlockInCacheHelper(
const Slice& block_contents, const BlockHandle* handle,
BlockType block_type) {
Status s;
switch (block_type) {
case BlockType::kData:
case BlockType::kIndex:
case BlockType::kFilterPartitionIndex:
s = InsertBlockInCache<Block>(block_contents, handle, block_type);
break;
case BlockType::kFilter:
s = InsertBlockInCache<ParsedFullFilterBlock>(block_contents, handle,
block_type);
break;
case BlockType::kCompressionDictionary:
s = InsertBlockInCache<UncompressionDict>(block_contents, handle,
block_type);
break;
default:
// no-op / not cached
break;
}
return s;
}
template <typename TBlocklike>
Status BlockBasedTableBuilder::InsertBlockInCache(const Slice& block_contents,
const BlockHandle* handle,
BlockType block_type) {
// Uncompressed regular block cache
Cache* block_cache = rep_->table_options.block_cache.get();
Status s;
if (block_cache != nullptr) {
size_t size = block_contents.size();
auto buf = AllocateBlock(size, block_cache->memory_allocator());
memcpy(buf.get(), block_contents.data(), size);
BlockContents results(std::move(buf), size);
CacheKey key = BlockBasedTable::GetCacheKey(rep_->base_cache_key, *handle);
const size_t read_amp_bytes_per_bit =
rep_->table_options.read_amp_bytes_per_bit;
// TODO akanksha:: Dedup below code by calling
// BlockBasedTable::PutDataBlockToCache.
std::unique_ptr<TBlocklike> block_holder(
BlocklikeTraits<TBlocklike>::Create(
std::move(results), read_amp_bytes_per_bit,
rep_->ioptions.statistics.get(),
false /*rep_->blocks_definitely_zstd_compressed*/,
rep_->table_options.filter_policy.get()));
assert(block_holder->own_bytes());
size_t charge = block_holder->ApproximateMemoryUsage();
s = block_cache->Insert(
key.AsSlice(), block_holder.get(),
BlocklikeTraits<TBlocklike>::GetCacheItemHelper(block_type), charge,
nullptr, Cache::Priority::LOW);
if (s.ok()) {
// Release ownership of block_holder.
block_holder.release();
BlockBasedTable::UpdateCacheInsertionMetrics(
block_type, nullptr /*get_context*/, charge, s.IsOkOverwritten(),
rep_->ioptions.stats);
} else {
RecordTick(rep_->ioptions.stats, BLOCK_CACHE_ADD_FAILURES);
}
}
return s;
}
void BlockBasedTableBuilder::WriteFilterBlock(
MetaIndexBuilder* meta_index_builder) {
if (rep_->filter_builder == nullptr || rep_->filter_builder->IsEmpty()) {
// No filter block needed
return;
}
BlockHandle filter_block_handle;
bool is_partitioned_filter = rep_->table_options.partition_filters;
if (ok()) {
rep_->props.num_filter_entries +=
rep_->filter_builder->EstimateEntriesAdded();
Status s = Status::Incomplete();
while (ok() && s.IsIncomplete()) {
// filter_data is used to store the transferred filter data payload from
// FilterBlockBuilder and deallocate the payload by going out of scope.
// Otherwise, the payload will unnecessarily remain until
// BlockBasedTableBuilder is deallocated.
//
// See FilterBlockBuilder::Finish() for more on the difference in
// transferred filter data payload among different FilterBlockBuilder
// subtypes.
std::unique_ptr<const char[]> filter_data;
Slice filter_content =
rep_->filter_builder->Finish(filter_block_handle, &s, &filter_data);
assert(s.ok() || s.IsIncomplete() || s.IsCorruption());
if (s.IsCorruption()) {
rep_->SetStatus(s);
break;
}
rep_->props.filter_size += filter_content.size();
BlockType btype = is_partitioned_filter && /* last */ s.ok()
? BlockType::kFilterPartitionIndex
: BlockType::kFilter;
WriteRawBlock(filter_content, kNoCompression, &filter_block_handle, btype,
nullptr /*raw_contents*/);
}
rep_->filter_builder->ResetFilterBitsBuilder();
}
if (ok()) {
// Add mapping from "<filter_block_prefix>.Name" to location
// of filter data.
std::string key;
key = is_partitioned_filter ? BlockBasedTable::kPartitionedFilterBlockPrefix
: BlockBasedTable::kFullFilterBlockPrefix;
key.append(rep_->table_options.filter_policy->CompatibilityName());
meta_index_builder->Add(key, filter_block_handle);
}
}
void BlockBasedTableBuilder::WriteIndexBlock(
MetaIndexBuilder* meta_index_builder, BlockHandle* index_block_handle) {
if (!ok()) {
return;
}
IndexBuilder::IndexBlocks index_blocks;
auto index_builder_status = rep_->index_builder->Finish(&index_blocks);
if (index_builder_status.IsIncomplete()) {
// We we have more than one index partition then meta_blocks are not
// supported for the index. Currently meta_blocks are used only by
// HashIndexBuilder which is not multi-partition.
assert(index_blocks.meta_blocks.empty());
} else if (ok() && !index_builder_status.ok()) {
rep_->SetStatus(index_builder_status);
}
if (ok()) {
for (const auto& item : index_blocks.meta_blocks) {
BlockHandle block_handle;
WriteBlock(item.second, &block_handle, BlockType::kIndex);
if (!ok()) {
break;
}
meta_index_builder->Add(item.first, block_handle);
}
}
if (ok()) {
if (rep_->table_options.enable_index_compression) {
WriteBlock(index_blocks.index_block_contents, index_block_handle,
BlockType::kIndex);
} else {
WriteRawBlock(index_blocks.index_block_contents, kNoCompression,
index_block_handle, BlockType::kIndex);
}
}
// If there are more index partitions, finish them and write them out
if (index_builder_status.IsIncomplete()) {
bool index_building_finished = false;
while (ok() && !index_building_finished) {
Status s =
rep_->index_builder->Finish(&index_blocks, *index_block_handle);
if (s.ok()) {
index_building_finished = true;
} else if (s.IsIncomplete()) {
// More partitioned index after this one
assert(!index_building_finished);
} else {
// Error
rep_->SetStatus(s);
return;
}
if (rep_->table_options.enable_index_compression) {
WriteBlock(index_blocks.index_block_contents, index_block_handle,
BlockType::kIndex);
} else {
WriteRawBlock(index_blocks.index_block_contents, kNoCompression,
index_block_handle, BlockType::kIndex);
}
// The last index_block_handle will be for the partition index block
}
}
}
void BlockBasedTableBuilder::WritePropertiesBlock(
MetaIndexBuilder* meta_index_builder) {
BlockHandle properties_block_handle;
if (ok()) {
PropertyBlockBuilder property_block_builder;
rep_->props.filter_policy_name =
rep_->table_options.filter_policy != nullptr
? rep_->table_options.filter_policy->Name()
: "";
rep_->props.index_size =
rep_->index_builder->IndexSize() + kBlockTrailerSize;
rep_->props.comparator_name = rep_->ioptions.user_comparator != nullptr
? rep_->ioptions.user_comparator->Name()
: "nullptr";
rep_->props.merge_operator_name =
rep_->ioptions.merge_operator != nullptr
? rep_->ioptions.merge_operator->Name()
: "nullptr";
rep_->props.compression_name =
CompressionTypeToString(rep_->compression_type);
rep_->props.compression_options =
CompressionOptionsToString(rep_->compression_opts);
rep_->props.prefix_extractor_name =
rep_->moptions.prefix_extractor != nullptr
? rep_->moptions.prefix_extractor->AsString()
: "nullptr";
std::string property_collectors_names = "[";
for (size_t i = 0;
i < rep_->ioptions.table_properties_collector_factories.size(); ++i) {
if (i != 0) {
property_collectors_names += ",";
}
property_collectors_names +=
rep_->ioptions.table_properties_collector_factories[i]->Name();
}
property_collectors_names += "]";
rep_->props.property_collectors_names = property_collectors_names;
if (rep_->table_options.index_type ==
BlockBasedTableOptions::kTwoLevelIndexSearch) {
assert(rep_->p_index_builder_ != nullptr);
rep_->props.index_partitions = rep_->p_index_builder_->NumPartitions();
rep_->props.top_level_index_size =
rep_->p_index_builder_->TopLevelIndexSize(rep_->offset);
}
rep_->props.index_key_is_user_key =
!rep_->index_builder->seperator_is_key_plus_seq();
rep_->props.index_value_is_delta_encoded =
rep_->use_delta_encoding_for_index_values;
if (rep_->sampled_input_data_bytes > 0) {
rep_->props.slow_compression_estimated_data_size = static_cast<uint64_t>(
static_cast<double>(rep_->sampled_output_slow_data_bytes) /
rep_->sampled_input_data_bytes *
rep_->compressible_input_data_bytes +
rep_->uncompressible_input_data_bytes + 0.5);
rep_->props.fast_compression_estimated_data_size = static_cast<uint64_t>(
static_cast<double>(rep_->sampled_output_fast_data_bytes) /
rep_->sampled_input_data_bytes *
rep_->compressible_input_data_bytes +
rep_->uncompressible_input_data_bytes + 0.5);
} else if (rep_->sample_for_compression > 0) {
// We tried to sample but none were found. Assume worst-case (compression
// ratio 1.0) so data is complete and aggregatable.
rep_->props.slow_compression_estimated_data_size =
rep_->compressible_input_data_bytes +
rep_->uncompressible_input_data_bytes;
rep_->props.fast_compression_estimated_data_size =
rep_->compressible_input_data_bytes +
rep_->uncompressible_input_data_bytes;
}
// Add basic properties
property_block_builder.AddTableProperty(rep_->props);
// Add use collected properties
NotifyCollectTableCollectorsOnFinish(rep_->table_properties_collectors,
rep_->ioptions.logger,
&property_block_builder);
Slice block_data = property_block_builder.Finish();
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::WritePropertiesBlock:BlockData", &block_data);
WriteRawBlock(block_data, kNoCompression, &properties_block_handle,
BlockType::kProperties);
}
if (ok()) {
#ifndef NDEBUG
{
uint64_t props_block_offset = properties_block_handle.offset();
uint64_t props_block_size = properties_block_handle.size();
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::WritePropertiesBlock:GetPropsBlockOffset",
&props_block_offset);
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::WritePropertiesBlock:GetPropsBlockSize",
&props_block_size);
}
#endif // !NDEBUG
const std::string* properties_block_meta = &kPropertiesBlockName;
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::WritePropertiesBlock:Meta",
&properties_block_meta);
meta_index_builder->Add(*properties_block_meta, properties_block_handle);
}
}
void BlockBasedTableBuilder::WriteCompressionDictBlock(
MetaIndexBuilder* meta_index_builder) {
if (rep_->compression_dict != nullptr &&
rep_->compression_dict->GetRawDict().size()) {
BlockHandle compression_dict_block_handle;
if (ok()) {
WriteRawBlock(rep_->compression_dict->GetRawDict(), kNoCompression,
&compression_dict_block_handle,
BlockType::kCompressionDictionary);
#ifndef NDEBUG
Slice compression_dict = rep_->compression_dict->GetRawDict();
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::WriteCompressionDictBlock:RawDict",
&compression_dict);
#endif // NDEBUG
}
if (ok()) {
meta_index_builder->Add(kCompressionDictBlockName,
compression_dict_block_handle);
}
}
}
void BlockBasedTableBuilder::WriteRangeDelBlock(
MetaIndexBuilder* meta_index_builder) {
if (ok() && !rep_->range_del_block.empty()) {
BlockHandle range_del_block_handle;
WriteRawBlock(rep_->range_del_block.Finish(), kNoCompression,
&range_del_block_handle, BlockType::kRangeDeletion);
meta_index_builder->Add(kRangeDelBlockName, range_del_block_handle);
}
}
void BlockBasedTableBuilder::WriteFooter(BlockHandle& metaindex_block_handle,
BlockHandle& index_block_handle) {
Rep* r = rep_;
// this is guaranteed by BlockBasedTableBuilder's constructor
assert(r->table_options.checksum == kCRC32c ||
r->table_options.format_version != 0);
assert(ok());
FooterBuilder footer;
footer.Build(kBlockBasedTableMagicNumber, r->table_options.format_version,
r->get_offset(), r->table_options.checksum,
metaindex_block_handle, index_block_handle);
IOStatus ios = r->file->Append(footer.GetSlice());
if (ios.ok()) {
r->set_offset(r->get_offset() + footer.GetSlice().size());
} else {
r->SetIOStatus(ios);
}
}
void BlockBasedTableBuilder::EnterUnbuffered() {
Rep* r = rep_;
assert(r->state == Rep::State::kBuffered);
r->state = Rep::State::kUnbuffered;
const size_t kSampleBytes = r->compression_opts.zstd_max_train_bytes > 0
? r->compression_opts.zstd_max_train_bytes
: r->compression_opts.max_dict_bytes;
const size_t kNumBlocksBuffered = r->data_block_buffers.size();
if (kNumBlocksBuffered == 0) {
// The below code is neither safe nor necessary for handling zero data
// blocks.
return;
}
// Abstract algebra teaches us that a finite cyclic group (such as the
// additive group of integers modulo N) can be generated by a number that is
// coprime with N. Since N is variable (number of buffered data blocks), we
// must then pick a prime number in order to guarantee coprimeness with any N.
//
// One downside of this approach is the spread will be poor when
// `kPrimeGeneratorRemainder` is close to zero or close to
// `kNumBlocksBuffered`.
//
// Picked a random number between one and one trillion and then chose the
// next prime number greater than or equal to it.
const uint64_t kPrimeGenerator = 545055921143ull;
// Can avoid repeated division by just adding the remainder repeatedly.
const size_t kPrimeGeneratorRemainder = static_cast<size_t>(
kPrimeGenerator % static_cast<uint64_t>(kNumBlocksBuffered));
const size_t kInitSampleIdx = kNumBlocksBuffered / 2;
std::string compression_dict_samples;
std::vector<size_t> compression_dict_sample_lens;
size_t buffer_idx = kInitSampleIdx;
for (size_t i = 0;
i < kNumBlocksBuffered && compression_dict_samples.size() < kSampleBytes;
++i) {
size_t copy_len = std::min(kSampleBytes - compression_dict_samples.size(),
r->data_block_buffers[buffer_idx].size());
compression_dict_samples.append(r->data_block_buffers[buffer_idx], 0,
copy_len);
compression_dict_sample_lens.emplace_back(copy_len);
buffer_idx += kPrimeGeneratorRemainder;
if (buffer_idx >= kNumBlocksBuffered) {
buffer_idx -= kNumBlocksBuffered;
}
}
// final data block flushed, now we can generate dictionary from the samples.
// OK if compression_dict_samples is empty, we'll just get empty dictionary.
std::string dict;
if (r->compression_opts.zstd_max_train_bytes > 0) {
if (r->compression_opts.use_zstd_dict_trainer) {
dict = ZSTD_TrainDictionary(compression_dict_samples,
compression_dict_sample_lens,
r->compression_opts.max_dict_bytes);
} else {
dict = ZSTD_FinalizeDictionary(
compression_dict_samples, compression_dict_sample_lens,
r->compression_opts.max_dict_bytes, r->compression_opts.level);
}
} else {
dict = std::move(compression_dict_samples);
}
r->compression_dict.reset(new CompressionDict(dict, r->compression_type,
r->compression_opts.level));
r->verify_dict.reset(new UncompressionDict(
dict, r->compression_type == kZSTD ||
r->compression_type == kZSTDNotFinalCompression));
auto get_iterator_for_block = [&r](size_t i) {
auto& data_block = r->data_block_buffers[i];
assert(!data_block.empty());
Block reader{BlockContents{data_block}};
DataBlockIter* iter = reader.NewDataIterator(
r->internal_comparator.user_comparator(), kDisableGlobalSequenceNumber);
iter->SeekToFirst();
assert(iter->Valid());
return std::unique_ptr<DataBlockIter>(iter);
};
std::unique_ptr<DataBlockIter> iter = nullptr, next_block_iter = nullptr;
for (size_t i = 0; ok() && i < r->data_block_buffers.size(); ++i) {
if (iter == nullptr) {
iter = get_iterator_for_block(i);
assert(iter != nullptr);
};
if (i + 1 < r->data_block_buffers.size()) {
next_block_iter = get_iterator_for_block(i + 1);
}
auto& data_block = r->data_block_buffers[i];
if (r->IsParallelCompressionEnabled()) {
Slice first_key_in_next_block;
const Slice* first_key_in_next_block_ptr = &first_key_in_next_block;
if (i + 1 < r->data_block_buffers.size()) {
assert(next_block_iter != nullptr);
first_key_in_next_block = next_block_iter->key();
} else {
first_key_in_next_block_ptr = r->first_key_in_next_block;
}
std::vector<std::string> keys;
for (; iter->Valid(); iter->Next()) {
keys.emplace_back(iter->key().ToString());
}
ParallelCompressionRep::BlockRep* block_rep = r->pc_rep->PrepareBlock(
r->compression_type, first_key_in_next_block_ptr, &data_block, &keys);
assert(block_rep != nullptr);
r->pc_rep->file_size_estimator.EmitBlock(block_rep->data->size(),
r->get_offset());
r->pc_rep->EmitBlock(block_rep);
} else {
for (; iter->Valid(); iter->Next()) {
Slice key = iter->key();
if (r->filter_builder != nullptr) {
size_t ts_sz =
r->internal_comparator.user_comparator()->timestamp_size();
r->filter_builder->Add(ExtractUserKeyAndStripTimestamp(key, ts_sz));
}
r->index_builder->OnKeyAdded(key);
}
WriteBlock(Slice(data_block), &r->pending_handle, BlockType::kData);
if (ok() && i + 1 < r->data_block_buffers.size()) {
assert(next_block_iter != nullptr);
Slice first_key_in_next_block = next_block_iter->key();
Slice* first_key_in_next_block_ptr = &first_key_in_next_block;
iter->SeekToLast();
std::string last_key = iter->key().ToString();
r->index_builder->AddIndexEntry(&last_key, first_key_in_next_block_ptr,
r->pending_handle);
}
}
std::swap(iter, next_block_iter);
}
r->data_block_buffers.clear();
r->data_begin_offset = 0;
// Release all reserved cache for data block buffers
if (r->compression_dict_buffer_cache_res_mgr != nullptr) {
Status s = r->compression_dict_buffer_cache_res_mgr->UpdateCacheReservation(
r->data_begin_offset);
s.PermitUncheckedError();
}
}
Status BlockBasedTableBuilder::Finish() {
Rep* r = rep_;
assert(r->state != Rep::State::kClosed);
bool empty_data_block = r->data_block.empty();
r->first_key_in_next_block = nullptr;
Flush();
if (r->state == Rep::State::kBuffered) {
EnterUnbuffered();
}
if (r->IsParallelCompressionEnabled()) {
StopParallelCompression();
#ifndef NDEBUG
for (const auto& br : r->pc_rep->block_rep_buf) {
assert(br.status.ok());
}
#endif // !NDEBUG
} else {
// To make sure properties block is able to keep the accurate size of index
// block, we will finish writing all index entries first.
if (ok() && !empty_data_block) {
r->index_builder->AddIndexEntry(
&r->last_key, nullptr /* no next data block */, r->pending_handle);
}
}
// Write meta blocks, metaindex block and footer in the following order.
// 1. [meta block: filter]
// 2. [meta block: index]
// 3. [meta block: compression dictionary]
// 4. [meta block: range deletion tombstone]
// 5. [meta block: properties]
// 6. [metaindex block]
// 7. Footer
BlockHandle metaindex_block_handle, index_block_handle;
MetaIndexBuilder meta_index_builder;
WriteFilterBlock(&meta_index_builder);
WriteIndexBlock(&meta_index_builder, &index_block_handle);
WriteCompressionDictBlock(&meta_index_builder);
WriteRangeDelBlock(&meta_index_builder);
WritePropertiesBlock(&meta_index_builder);
if (ok()) {
// flush the meta index block
WriteRawBlock(meta_index_builder.Finish(), kNoCompression,
&metaindex_block_handle, BlockType::kMetaIndex);
}
if (ok()) {
WriteFooter(metaindex_block_handle, index_block_handle);
}
r->state = Rep::State::kClosed;
r->SetStatus(r->CopyIOStatus());
Status ret_status = r->CopyStatus();
assert(!ret_status.ok() || io_status().ok());
return ret_status;
}
void BlockBasedTableBuilder::Abandon() {
assert(rep_->state != Rep::State::kClosed);
if (rep_->IsParallelCompressionEnabled()) {
StopParallelCompression();
}
rep_->state = Rep::State::kClosed;
rep_->CopyStatus().PermitUncheckedError();
rep_->CopyIOStatus().PermitUncheckedError();
}
uint64_t BlockBasedTableBuilder::NumEntries() const {
return rep_->props.num_entries;
}
bool BlockBasedTableBuilder::IsEmpty() const {
return rep_->props.num_entries == 0 && rep_->props.num_range_deletions == 0;
}
uint64_t BlockBasedTableBuilder::FileSize() const { return rep_->offset; }
uint64_t BlockBasedTableBuilder::EstimatedFileSize() const {
if (rep_->IsParallelCompressionEnabled()) {
// Use compression ratio so far and inflight raw bytes to estimate
// final SST size.
return rep_->pc_rep->file_size_estimator.GetEstimatedFileSize();
} else {
return FileSize();
}
}
bool BlockBasedTableBuilder::NeedCompact() const {
for (const auto& collector : rep_->table_properties_collectors) {
if (collector->NeedCompact()) {
return true;
}
}
return false;
}
TableProperties BlockBasedTableBuilder::GetTableProperties() const {
TableProperties ret = rep_->props;
for (const auto& collector : rep_->table_properties_collectors) {
for (const auto& prop : collector->GetReadableProperties()) {
ret.readable_properties.insert(prop);
}
collector->Finish(&ret.user_collected_properties).PermitUncheckedError();
}
return ret;
}
std::string BlockBasedTableBuilder::GetFileChecksum() const {
if (rep_->file != nullptr) {
return rep_->file->GetFileChecksum();
} else {
return kUnknownFileChecksum;
}
}
const char* BlockBasedTableBuilder::GetFileChecksumFuncName() const {
if (rep_->file != nullptr) {
return rep_->file->GetFileChecksumFuncName();
} else {
return kUnknownFileChecksumFuncName;
}
}
void BlockBasedTableBuilder::SetSeqnoTimeTableProperties(
const std::string& encoded_seqno_to_time_mapping,
uint64_t oldest_ancestor_time) {
rep_->props.seqno_to_time_mapping = encoded_seqno_to_time_mapping;
rep_->props.creation_time = oldest_ancestor_time;
}
const std::string BlockBasedTable::kObsoleteFilterBlockPrefix = "filter.";
const std::string BlockBasedTable::kFullFilterBlockPrefix = "fullfilter.";
const std::string BlockBasedTable::kPartitionedFilterBlockPrefix =
"partitionedfilter.";
} // namespace ROCKSDB_NAMESPACE