rocksdb/table/block_based/block_based_table_builder.cc
Andrew Kryczka daca92c17a Pick samples for compression dictionary using prime number (#7987)
Summary:
The sample selection technique taken in https://github.com/facebook/rocksdb/issues/7970 was problematic
because it had two code paths for sample selection depending on the
number of data blocks, and one of those code paths involved an
allocation. Using prime numbers, we can consolidate into one code path
without allocation. The downside is there will be values of N (number of
data blocks buffered) that suffer from poor spread in the selected
samples.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7987

Test Plan: `make check -j48`

Reviewed By: pdillinger

Differential Revision: D26586147

Pulled By: ajkr

fbshipit-source-id: 62028e54336fadb6e2c7a7fe6747daa05a263d32
2021-02-22 17:43:03 -08:00

1872 lines
70 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).
//
// 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 "db/dbformat.h"
#include "index_builder.h"
#include "memory/memory_allocator.h"
#include "rocksdb/cache.h"
#include "rocksdb/comparator.h"
#include "rocksdb/env.h"
#include "rocksdb/flush_block_policy.h"
#include "rocksdb/merge_operator.h"
#include "rocksdb/table.h"
#include "table/block_based/block.h"
#include "table/block_based/block_based_filter_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/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/table_builder.h"
#include "util/coding.h"
#include "util/compression.h"
#include "util/crc32c.h"
#include "util/stop_watch.h"
#include "util/string_util.h"
#include "util/work_queue.h"
#include "util/xxhash.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 {
// 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;
if (table_opt.filter_policy == nullptr) return nullptr;
FilterBitsBuilder* filter_bits_builder =
BloomFilterPolicy::GetBuilderFromContext(context);
if (filter_bits_builder == nullptr) {
return new BlockBasedFilterBlockBuilder(mopt.prefix_extractor.get(),
table_opt);
} 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 /* blockRawBytes */,
uint64_t /* blockCompressedBytesFast */,
uint64_t /* blockCompressedBytesSlow */) 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 ImmutableCFOptions 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 and keys to replay later. Needed when
// compression dictionary is enabled so we can finalize the dictionary before
// compressing any data blocks.
// TODO(ajkr): ideally we don't buffer all keys and all uncompressed data
// blocks as it's redundant, but it's easier to implement for now.
std::vector<std::pair<std::string, std::vector<std::string>>>
data_block_and_keys_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;
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_and_keys_buffers`) does not exceed
// `buffer_limit`.
uint64_t buffer_limit;
const bool use_delta_encoding_for_index_values;
std::unique_ptr<FilterBlockBuilder> filter_builder;
char compressed_cache_key_prefix[BlockBasedTable::kMaxCacheKeyPrefixSize];
size_t compressed_cache_key_prefix_size;
BlockHandle pending_handle; // Handle to add to index block
std::string compressed_output;
std::unique_ptr<FlushBlockPolicy> flush_block_policy;
int level_at_creation;
uint32_t column_family_id;
const std::string& column_family_name;
uint64_t creation_time = 0;
uint64_t oldest_key_time = 0;
uint64_t file_creation_time = 0;
// DB IDs
const std::string db_id;
const std::string db_session_id;
std::string db_host_id;
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.
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);
}
}
Rep(const ImmutableCFOptions& _ioptions, const MutableCFOptions& _moptions,
const BlockBasedTableOptions& table_opt,
const InternalKeyComparator& icomparator,
const std::vector<std::unique_ptr<IntTblPropCollectorFactory>>*
int_tbl_prop_collector_factories,
uint32_t _column_family_id, WritableFileWriter* f,
const CompressionType _compression_type,
const uint64_t _sample_for_compression,
const CompressionOptions& _compression_opts, const bool skip_filters,
const int _level_at_creation, const std::string& _column_family_name,
const uint64_t _creation_time, const uint64_t _oldest_key_time,
const uint64_t target_file_size, const uint64_t _file_creation_time,
const std::string& _db_id, const std::string& _db_session_id)
: ioptions(_ioptions),
moptions(_moptions),
table_options(table_opt),
internal_comparator(icomparator),
file(f),
offset(0),
alignment(table_options.block_align
? std::min(table_options.block_size, kDefaultPageSize)
: 0),
data_block(table_options.block_restart_interval,
table_options.use_delta_encoding,
false /* use_value_delta_encoding */,
icomparator.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(_moptions.prefix_extractor.get()),
compression_type(_compression_type),
sample_for_compression(_sample_for_compression),
compression_opts(_compression_opts),
compression_dict(),
compression_ctxs(_compression_opts.parallel_threads),
verify_ctxs(_compression_opts.parallel_threads),
verify_dict(),
state((_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),
compressed_cache_key_prefix_size(0),
flush_block_policy(
table_options.flush_block_policy_factory->NewFlushBlockPolicy(
table_options, data_block)),
level_at_creation(_level_at_creation),
column_family_id(_column_family_id),
column_family_name(_column_family_name),
creation_time(_creation_time),
oldest_key_time(_oldest_key_time),
file_creation_time(_file_creation_time),
db_id(_db_id),
db_session_id(_db_session_id),
db_host_id(ioptions.db_host_id),
status_ok(true),
io_status_ok(true) {
if (target_file_size == 0) {
buffer_limit = compression_opts.max_dict_buffer_bytes;
} else if (compression_opts.max_dict_buffer_bytes == 0) {
buffer_limit = target_file_size;
} else {
buffer_limit =
std::min(target_file_size, compression_opts.max_dict_buffer_bytes);
}
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 (skip_filters) {
filter_builder = nullptr;
} else {
FilterBuildingContext context(table_options);
context.column_family_name = column_family_name;
context.compaction_style = ioptions.compaction_style;
context.level_at_creation = level_at_creation;
context.info_log = ioptions.info_log;
filter_builder.reset(CreateFilterBlockBuilder(
ioptions, moptions, context, use_delta_encoding_for_index_values,
p_index_builder_));
}
for (auto& collector_factories : *int_tbl_prop_collector_factories) {
table_properties_collectors.emplace_back(
collector_factories->CreateIntTblPropCollector(column_family_id));
}
table_properties_collectors.emplace_back(
new BlockBasedTablePropertiesCollector(
table_options.index_type, table_options.whole_key_filtering,
_moptions.prefix_extractor != nullptr));
if (table_options.verify_compression) {
for (uint32_t i = 0; i < compression_opts.parallel_threads; i++) {
verify_ctxs[i].reset(new UncompressionContext(compression_type));
}
}
if (!ReifyDbHostIdProperty(ioptions.env, &db_host_id).ok()) {
ROCKS_LOG_INFO(ioptions.info_log, "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.
typedef std::vector<BlockRep> BlockRepBuffer;
BlockRepBuffer block_rep_buf;
// Use a thread-safe queue for concurrent access from block
// building thread and writer thread.
typedef WorkQueue<BlockRep*> BlockRepPool;
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.
typedef WorkQueue<BlockRep*> CompressQueue;
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.
typedef WorkQueue<BlockRepSlot*> WriteQueue;
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 ImmutableCFOptions& ioptions, const MutableCFOptions& moptions,
const BlockBasedTableOptions& table_options,
const InternalKeyComparator& internal_comparator,
const std::vector<std::unique_ptr<IntTblPropCollectorFactory>>*
int_tbl_prop_collector_factories,
uint32_t column_family_id, WritableFileWriter* file,
const CompressionType compression_type,
const uint64_t sample_for_compression,
const CompressionOptions& compression_opts, const bool skip_filters,
const std::string& column_family_name, const int level_at_creation,
const uint64_t creation_time, const uint64_t oldest_key_time,
const uint64_t target_file_size, const uint64_t file_creation_time,
const std::string& db_id, const std::string& db_session_id) {
BlockBasedTableOptions sanitized_table_options(table_options);
if (sanitized_table_options.format_version == 0 &&
sanitized_table_options.checksum != kCRC32c) {
ROCKS_LOG_WARN(
ioptions.info_log,
"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(
ioptions, moptions, sanitized_table_options, internal_comparator,
int_tbl_prop_collector_factories, column_family_id, file,
compression_type, sample_for_compression, compression_opts, skip_filters,
level_at_creation, column_family_name, creation_time, oldest_key_time,
target_file_size, file_creation_time, db_id, db_session_id);
if (rep_->filter_builder != nullptr) {
rep_->filter_builder->StartBlock(0);
}
if (table_options.block_cache_compressed.get() != nullptr) {
BlockBasedTable::GenerateCachePrefix<Cache, FSWritableFile>(
table_options.block_cache_compressed.get(), file->writable_file(),
&rep_->compressed_cache_key_prefix[0],
&rep_->compressed_cache_key_prefix_size);
}
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 && r->buffer_limit != 0 &&
r->data_begin_offset > r->buffer_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->last_key.assign(key.data(), key.size());
r->data_block.Add(key, value);
if (r->state == Rep::State::kBuffered) {
// Buffer keys to be replayed during `Finish()` once compression
// dictionary has been finalized.
if (r->data_block_and_keys_buffers.empty() || should_flush) {
r->data_block_and_keys_buffers.emplace_back();
}
r->data_block_and_keys_buffers.back().second.emplace_back(key.ToString());
} 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.info_log);
} 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.info_log);
} 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, true /* is_data_block */);
}
}
void BlockBasedTableBuilder::WriteBlock(BlockBuilder* block,
BlockHandle* handle,
bool is_data_block) {
block->Finish();
std::string raw_block_contents;
block->SwapAndReset(raw_block_contents);
if (rep_->state == Rep::State::kBuffered) {
assert(is_data_block);
assert(!rep_->data_block_and_keys_buffers.empty());
rep_->data_block_and_keys_buffers.back().first =
std::move(raw_block_contents);
rep_->data_begin_offset +=
rep_->data_block_and_keys_buffers.back().first.size();
return;
}
WriteBlock(raw_block_contents, handle, is_data_block);
}
void BlockBasedTableBuilder::WriteBlock(const Slice& raw_block_contents,
BlockHandle* handle,
bool is_data_block) {
Rep* r = rep_;
assert(r->state == Rep::State::kUnbuffered);
Slice block_contents;
CompressionType type;
Status compress_status;
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, is_data_block);
r->compressed_output.clear();
if (is_data_block) {
if (r->filter_builder != nullptr) {
r->filter_builder->StartBlock(r->get_offset());
}
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.env->GetSystemClock(),
ShouldReportDetailedTime(r->ioptions.env, r->ioptions.statistics));
if (is_status_ok && raw_block_contents.size() < kCompressionSizeLimit) {
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);
// 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.info_log,
"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.
abort_compression = true;
}
// Abort compression if the block is too big, or did not pass
// verification.
if (abort_compression) {
RecordTick(r->ioptions.statistics, NUMBER_BLOCK_NOT_COMPRESSED);
*type = kNoCompression;
*block_contents = raw_block_contents;
} else if (*type != kNoCompression) {
if (ShouldReportDetailedTime(r->ioptions.env, r->ioptions.statistics)) {
RecordTimeToHistogram(r->ioptions.statistics, COMPRESSION_TIMES_NANOS,
timer.ElapsedNanos());
}
RecordInHistogram(r->ioptions.statistics, BYTES_COMPRESSED,
raw_block_contents.size());
RecordTick(r->ioptions.statistics, NUMBER_BLOCK_COMPRESSED);
} else if (*type != r->compression_type) {
RecordTick(r->ioptions.statistics, NUMBER_BLOCK_NOT_COMPRESSED);
}
}
void BlockBasedTableBuilder::WriteRawBlock(const Slice& block_contents,
CompressionType type,
BlockHandle* handle,
bool is_data_block) {
Rep* r = rep_;
Status s = Status::OK();
IOStatus io_s = IOStatus::OK();
StopWatch sw(r->ioptions.env->GetSystemClock(), r->ioptions.statistics,
WRITE_RAW_BLOCK_MICROS);
handle->set_offset(r->get_offset());
handle->set_size(block_contents.size());
assert(status().ok());
assert(io_status().ok());
io_s = r->file->Append(block_contents);
if (io_s.ok()) {
char trailer[kBlockTrailerSize];
trailer[0] = type;
uint32_t checksum = 0;
switch (r->table_options.checksum) {
case kNoChecksum:
break;
case kCRC32c: {
uint32_t crc =
crc32c::Value(block_contents.data(), block_contents.size());
// Extend to cover compression type
crc = crc32c::Extend(crc, trailer, 1);
checksum = crc32c::Mask(crc);
break;
}
case kxxHash: {
XXH32_state_t* const state = XXH32_createState();
XXH32_reset(state, 0);
XXH32_update(state, block_contents.data(), block_contents.size());
// Extend to cover compression type
XXH32_update(state, trailer, 1);
checksum = XXH32_digest(state);
XXH32_freeState(state);
break;
}
case kxxHash64: {
XXH64_state_t* const state = XXH64_createState();
XXH64_reset(state, 0);
XXH64_update(state, block_contents.data(), block_contents.size());
// Extend to cover compression type
XXH64_update(state, trailer, 1);
checksum = Lower32of64(XXH64_digest(state));
XXH64_freeState(state);
break;
}
default:
assert(false);
break;
}
EncodeFixed32(trailer + 1, checksum);
assert(io_s.ok());
TEST_SYNC_POINT_CALLBACK(
"BlockBasedTableBuilder::WriteRawBlock:TamperWithChecksum",
static_cast<char*>(trailer));
io_s = r->file->Append(Slice(trailer, kBlockTrailerSize));
if (io_s.ok()) {
assert(s.ok());
s = InsertBlockInCache(block_contents, type, handle);
if (!s.ok()) {
r->SetStatus(s);
}
} else {
r->SetIOStatus(io_s);
}
if (s.ok() && io_s.ok()) {
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);
io_s = r->file->Pad(pad_bytes);
if (io_s.ok()) {
r->set_offset(r->get_offset() + pad_bytes);
} else {
r->SetIOStatus(io_s);
}
}
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());
}
}
}
} else {
r->SetIOStatus(io_s);
}
if (!io_s.ok() && s.ok()) {
r->SetStatus(io_s);
}
}
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, true /* is_data_block*/);
if (!ok()) {
break;
}
if (r->filter_builder != nullptr) {
r->filter_builder->StartBlock(r->get_offset());
}
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();
}
static void DeleteCachedBlockContents(const Slice& /*key*/, void* value) {
BlockContents* bc = reinterpret_cast<BlockContents*>(value);
delete bc;
}
//
// Make a copy of the block contents and insert into compressed block cache
//
Status BlockBasedTableBuilder::InsertBlockInCache(const Slice& block_contents,
const CompressionType type,
const BlockHandle* handle) {
Rep* r = rep_;
Cache* block_cache_compressed = r->table_options.block_cache_compressed.get();
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
// make cache key by appending the file offset to the cache prefix id
char* end = EncodeVarint64(
r->compressed_cache_key_prefix + r->compressed_cache_key_prefix_size,
handle->offset());
Slice key(r->compressed_cache_key_prefix,
static_cast<size_t>(end - r->compressed_cache_key_prefix));
// Insert into compressed block cache.
// How should we deal with compressed cache full?
block_cache_compressed
->Insert(key, block_contents_to_cache,
block_contents_to_cache->ApproximateMemoryUsage(),
&DeleteCachedBlockContents)
.PermitUncheckedError();
// Invalidate OS cache.
r->file->InvalidateCache(static_cast<size_t>(r->get_offset()), size)
.PermitUncheckedError();
}
return Status::OK();
}
void BlockBasedTableBuilder::WriteFilterBlock(
MetaIndexBuilder* meta_index_builder) {
BlockHandle filter_block_handle;
bool empty_filter_block = (rep_->filter_builder == nullptr ||
rep_->filter_builder->NumAdded() == 0);
if (ok() && !empty_filter_block) {
Status s = Status::Incomplete();
while (ok() && s.IsIncomplete()) {
Slice filter_content =
rep_->filter_builder->Finish(filter_block_handle, &s);
assert(s.ok() || s.IsIncomplete());
rep_->props.filter_size += filter_content.size();
WriteRawBlock(filter_content, kNoCompression, &filter_block_handle);
}
}
if (ok() && !empty_filter_block) {
// Add mapping from "<filter_block_prefix>.Name" to location
// of filter data.
std::string key;
if (rep_->filter_builder->IsBlockBased()) {
key = BlockBasedTable::kFilterBlockPrefix;
} else {
key = rep_->table_options.partition_filters
? BlockBasedTable::kPartitionedFilterBlockPrefix
: BlockBasedTable::kFullFilterBlockPrefix;
}
key.append(rep_->table_options.filter_policy->Name());
meta_index_builder->Add(key, filter_block_handle);
}
}
void BlockBasedTableBuilder::WriteIndexBlock(
MetaIndexBuilder* meta_index_builder, BlockHandle* index_block_handle) {
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, false /* is_data_block */);
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, false);
} else {
WriteRawBlock(index_blocks.index_block_contents, kNoCompression,
index_block_handle);
}
}
// If there are more index partitions, finish them and write them out
if (index_builder_status.IsIncomplete()) {
Status s = Status::Incomplete();
while (ok() && s.IsIncomplete()) {
s = rep_->index_builder->Finish(&index_blocks, *index_block_handle);
if (!s.ok() && !s.IsIncomplete()) {
rep_->SetStatus(s);
return;
}
if (rep_->table_options.enable_index_compression) {
WriteBlock(index_blocks.index_block_contents, index_block_handle,
false);
} else {
WriteRawBlock(index_blocks.index_block_contents, kNoCompression,
index_block_handle);
}
// 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.column_family_id = rep_->column_family_id;
rep_->props.column_family_name = rep_->column_family_name;
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->Name()
: "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;
rep_->props.creation_time = rep_->creation_time;
rep_->props.oldest_key_time = rep_->oldest_key_time;
rep_->props.file_creation_time = rep_->file_creation_time;
rep_->props.db_id = rep_->db_id;
rep_->props.db_session_id = rep_->db_session_id;
rep_->props.db_host_id = rep_->db_host_id;
// Add basic properties
property_block_builder.AddTableProperty(rep_->props);
// Add use collected properties
NotifyCollectTableCollectorsOnFinish(rep_->table_properties_collectors,
rep_->ioptions.info_log,
&property_block_builder);
WriteRawBlock(property_block_builder.Finish(), kNoCompression,
&properties_block_handle);
}
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
meta_index_builder->Add(kPropertiesBlock, 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);
#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(kCompressionDictBlock,
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);
meta_index_builder->Add(kRangeDelBlock, range_del_block_handle);
}
}
void BlockBasedTableBuilder::WriteFooter(BlockHandle& metaindex_block_handle,
BlockHandle& index_block_handle) {
Rep* r = rep_;
// No need to write out new footer if we're using default checksum.
// We're writing legacy magic number because we want old versions of RocksDB
// be able to read files generated with new release (just in case if
// somebody wants to roll back after an upgrade)
// TODO(icanadi) at some point in the future, when we're absolutely sure
// nobody will roll back to RocksDB 2.x versions, retire the legacy magic
// number and always write new table files with new magic number
bool legacy = (r->table_options.format_version == 0);
// this is guaranteed by BlockBasedTableBuilder's constructor
assert(r->table_options.checksum == kCRC32c ||
r->table_options.format_version != 0);
Footer footer(
legacy ? kLegacyBlockBasedTableMagicNumber : kBlockBasedTableMagicNumber,
r->table_options.format_version);
footer.set_metaindex_handle(metaindex_block_handle);
footer.set_index_handle(index_block_handle);
footer.set_checksum(r->table_options.checksum);
std::string footer_encoding;
footer.EncodeTo(&footer_encoding);
assert(ok());
IOStatus ios = r->file->Append(footer_encoding);
if (ios.ok()) {
r->set_offset(r->get_offset() + footer_encoding.size());
} else {
r->SetIOStatus(ios);
r->SetStatus(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_and_keys_buffers.size();
// 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_and_keys_buffers[buffer_idx].first.size());
compression_dict_samples.append(
r->data_block_and_keys_buffers[buffer_idx].first, 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) {
dict = ZSTD_TrainDictionary(compression_dict_samples,
compression_dict_sample_lens,
r->compression_opts.max_dict_bytes);
} 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));
for (size_t i = 0; ok() && i < r->data_block_and_keys_buffers.size(); ++i) {
auto& data_block = r->data_block_and_keys_buffers[i].first;
auto& keys = r->data_block_and_keys_buffers[i].second;
assert(!data_block.empty());
assert(!keys.empty());
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_and_keys_buffers.size()) {
first_key_in_next_block =
r->data_block_and_keys_buffers[i + 1].second.front();
} else {
first_key_in_next_block_ptr = r->first_key_in_next_block;
}
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 (const auto& key : keys) {
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,
true /* is_data_block */);
if (ok() && i + 1 < r->data_block_and_keys_buffers.size()) {
Slice first_key_in_next_block =
r->data_block_and_keys_buffers[i + 1].second.front();
Slice* first_key_in_next_block_ptr = &first_key_in_next_block;
r->index_builder->AddIndexEntry(
&keys.back(), first_key_in_next_block_ptr, r->pending_handle);
}
}
}
r->data_block_and_keys_buffers.clear();
}
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);
}
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;
}
}
const std::string BlockBasedTable::kFilterBlockPrefix = "filter.";
const std::string BlockBasedTable::kFullFilterBlockPrefix = "fullfilter.";
const std::string BlockBasedTable::kPartitionedFilterBlockPrefix =
"partitionedfilter.";
} // namespace ROCKSDB_NAMESPACE