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rocksdb/db/external_sst_file_ingestion...

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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#ifndef ROCKSDB_LITE
#include "db/external_sst_file_ingestion_job.h"
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
#include <algorithm>
#include <string>
#include <vector>
#include "db/version_edit.h"
#include "table/merging_iterator.h"
#include "table/scoped_arena_iterator.h"
#include "table/sst_file_writer_collectors.h"
#include "table/table_builder.h"
#include "util/file_reader_writer.h"
#include "util/file_util.h"
#include "util/stop_watch.h"
#include "util/sync_point.h"
namespace rocksdb {
Status ExternalSstFileIngestionJob::Prepare(
const std::vector<std::string>& external_files_paths) {
Status status;
// Read the information of files we are ingesting
for (const std::string& file_path : external_files_paths) {
IngestedFileInfo file_to_ingest;
status = GetIngestedFileInfo(file_path, &file_to_ingest);
if (!status.ok()) {
return status;
}
files_to_ingest_.push_back(file_to_ingest);
}
for (const IngestedFileInfo& f : files_to_ingest_) {
if (f.cf_id !=
TablePropertiesCollectorFactory::Context::kUnknownColumnFamily &&
f.cf_id != cfd_->GetID()) {
return Status::InvalidArgument(
"External file column family id dont match");
}
}
const Comparator* ucmp = cfd_->internal_comparator().user_comparator();
auto num_files = files_to_ingest_.size();
if (num_files == 0) {
return Status::InvalidArgument("The list of files is empty");
} else if (num_files > 1) {
// Verify that passed files dont have overlapping ranges
autovector<const IngestedFileInfo*> sorted_files;
for (size_t i = 0; i < num_files; i++) {
sorted_files.push_back(&files_to_ingest_[i]);
}
std::sort(
sorted_files.begin(), sorted_files.end(),
[&ucmp](const IngestedFileInfo* info1, const IngestedFileInfo* info2) {
return ucmp->Compare(info1->smallest_user_key,
info2->smallest_user_key) < 0;
});
for (size_t i = 0; i < num_files - 1; i++) {
if (ucmp->Compare(sorted_files[i]->largest_user_key,
sorted_files[i + 1]->smallest_user_key) >= 0) {
return Status::NotSupported("Files have overlapping ranges");
}
}
}
for (IngestedFileInfo& f : files_to_ingest_) {
if (f.num_entries == 0) {
return Status::InvalidArgument("File contain no entries");
}
if (!f.smallest_internal_key().Valid() ||
!f.largest_internal_key().Valid()) {
return Status::Corruption("Generated table have corrupted keys");
}
}
// Copy/Move external files into DB
for (IngestedFileInfo& f : files_to_ingest_) {
f.fd = FileDescriptor(versions_->NewFileNumber(), 0, f.file_size);
const std::string path_outside_db = f.external_file_path;
const std::string path_inside_db =
TableFileName(db_options_.db_paths, f.fd.GetNumber(), f.fd.GetPathId());
if (ingestion_options_.move_files) {
status = env_->LinkFile(path_outside_db, path_inside_db);
if (status.IsNotSupported()) {
// Original file is on a different FS, use copy instead of hard linking
status = CopyFile(env_, path_outside_db, path_inside_db, 0,
db_options_.use_fsync);
}
} else {
status = CopyFile(env_, path_outside_db, path_inside_db, 0,
db_options_.use_fsync);
}
TEST_SYNC_POINT("DBImpl::AddFile:FileCopied");
if (!status.ok()) {
break;
}
f.internal_file_path = path_inside_db;
}
if (!status.ok()) {
// We failed, remove all files that we copied into the db
for (IngestedFileInfo& f : files_to_ingest_) {
if (f.internal_file_path == "") {
break;
}
Status s = env_->DeleteFile(f.internal_file_path);
if (!s.ok()) {
ROCKS_LOG_WARN(db_options_.info_log,
"AddFile() clean up for file %s failed : %s",
f.internal_file_path.c_str(), s.ToString().c_str());
}
}
}
return status;
}
Status ExternalSstFileIngestionJob::NeedsFlush(bool* flush_needed,
SuperVersion* super_version) {
autovector<Range> ranges;
for (const IngestedFileInfo& file_to_ingest : files_to_ingest_) {
ranges.emplace_back(file_to_ingest.smallest_user_key,
file_to_ingest.largest_user_key);
}
Status status =
cfd_->RangesOverlapWithMemtables(ranges, super_version, flush_needed);
if (status.ok() && *flush_needed &&
!ingestion_options_.allow_blocking_flush) {
status = Status::InvalidArgument("External file requires flush");
}
return status;
}
Optimize for serial commits in 2PC Summary: Throughput: 46k tps in our sysbench settings (filling the details later) The idea is to have the simplest change that gives us a reasonable boost in 2PC throughput. Major design changes: 1. The WAL file internal buffer is not flushed after each write. Instead it is flushed before critical operations (WAL copy via fs) or when FlushWAL is called by MySQL. Flushing the WAL buffer is also protected via mutex_. 2. Use two sequence numbers: last seq, and last seq for write. Last seq is the last visible sequence number for reads. Last seq for write is the next sequence number that should be used to write to WAL/memtable. This allows to have a memtable write be in parallel to WAL writes. 3. BatchGroup is not used for writes. This means that we can have parallel writers which changes a major assumption in the code base. To accommodate for that i) allow only 1 WriteImpl that intends to write to memtable via mem_mutex_--which is fine since in 2PC almost all of the memtable writes come via group commit phase which is serial anyway, ii) make all the parts in the code base that assumed to be the only writer (via EnterUnbatched) to also acquire mem_mutex_, iii) stat updates are protected via a stat_mutex_. Note: the first commit has the approach figured out but is not clean. Submitting the PR anyway to get the early feedback on the approach. If we are ok with the approach I will go ahead with this updates: 0) Rebase with Yi's pipelining changes 1) Currently batching is disabled by default to make sure that it will be consistent with all unit tests. Will make this optional via a config. 2) A couple of unit tests are disabled. They need to be updated with the serial commit of 2PC taken into account. 3) Replacing BatchGroup with mem_mutex_ got a bit ugly as it requires releasing mutex_ beforehand (the same way EnterUnbatched does). This needs to be cleaned up. Closes https://github.com/facebook/rocksdb/pull/2345 Differential Revision: D5210732 Pulled By: maysamyabandeh fbshipit-source-id: 78653bd95a35cd1e831e555e0e57bdfd695355a4
7 years ago
// REQUIRES: we have become the only writer by entering both write_thread_ and
// nonmem_write_thread_
Status ExternalSstFileIngestionJob::Run() {
Status status;
SuperVersion* super_version = cfd_->GetSuperVersion();
#ifndef NDEBUG
// We should never run the job with a memtable that is overlapping
// with the files we are ingesting
bool need_flush = false;
status = NeedsFlush(&need_flush, super_version);
assert(status.ok() && need_flush == false);
#endif
bool consumed_seqno = false;
bool force_global_seqno = false;
if (ingestion_options_.snapshot_consistency && !db_snapshots_->empty()) {
// We need to assign a global sequence number to all the files even
// if the dont overlap with any ranges since we have snapshots
force_global_seqno = true;
}
// It is safe to use this instead of LastAllocatedSequence since we are
Optimize for serial commits in 2PC Summary: Throughput: 46k tps in our sysbench settings (filling the details later) The idea is to have the simplest change that gives us a reasonable boost in 2PC throughput. Major design changes: 1. The WAL file internal buffer is not flushed after each write. Instead it is flushed before critical operations (WAL copy via fs) or when FlushWAL is called by MySQL. Flushing the WAL buffer is also protected via mutex_. 2. Use two sequence numbers: last seq, and last seq for write. Last seq is the last visible sequence number for reads. Last seq for write is the next sequence number that should be used to write to WAL/memtable. This allows to have a memtable write be in parallel to WAL writes. 3. BatchGroup is not used for writes. This means that we can have parallel writers which changes a major assumption in the code base. To accommodate for that i) allow only 1 WriteImpl that intends to write to memtable via mem_mutex_--which is fine since in 2PC almost all of the memtable writes come via group commit phase which is serial anyway, ii) make all the parts in the code base that assumed to be the only writer (via EnterUnbatched) to also acquire mem_mutex_, iii) stat updates are protected via a stat_mutex_. Note: the first commit has the approach figured out but is not clean. Submitting the PR anyway to get the early feedback on the approach. If we are ok with the approach I will go ahead with this updates: 0) Rebase with Yi's pipelining changes 1) Currently batching is disabled by default to make sure that it will be consistent with all unit tests. Will make this optional via a config. 2) A couple of unit tests are disabled. They need to be updated with the serial commit of 2PC taken into account. 3) Replacing BatchGroup with mem_mutex_ got a bit ugly as it requires releasing mutex_ beforehand (the same way EnterUnbatched does). This needs to be cleaned up. Closes https://github.com/facebook/rocksdb/pull/2345 Differential Revision: D5210732 Pulled By: maysamyabandeh fbshipit-source-id: 78653bd95a35cd1e831e555e0e57bdfd695355a4
7 years ago
// the only active writer, and hence they are equal
const SequenceNumber last_seqno = versions_->LastSequence();
edit_.SetColumnFamily(cfd_->GetID());
// The levels that the files will be ingested into
for (IngestedFileInfo& f : files_to_ingest_) {
SequenceNumber assigned_seqno = 0;
if (ingestion_options_.ingest_behind) {
status = CheckLevelForIngestedBehindFile(&f);
} else {
status = AssignLevelAndSeqnoForIngestedFile(
super_version, force_global_seqno, cfd_->ioptions()->compaction_style,
&f, &assigned_seqno);
}
if (!status.ok()) {
return status;
}
status = AssignGlobalSeqnoForIngestedFile(&f, assigned_seqno);
TEST_SYNC_POINT_CALLBACK("ExternalSstFileIngestionJob::Run",
&assigned_seqno);
if (assigned_seqno == last_seqno + 1) {
consumed_seqno = true;
}
if (!status.ok()) {
return status;
}
edit_.AddFile(f.picked_level, f.fd.GetNumber(), f.fd.GetPathId(),
f.fd.GetFileSize(), f.smallest_internal_key(),
f.largest_internal_key(), f.assigned_seqno, f.assigned_seqno,
false);
}
if (consumed_seqno) {
versions_->SetLastAllocatedSequence(last_seqno + 1);
versions_->SetLastPublishedSequence(last_seqno + 1);
versions_->SetLastSequence(last_seqno + 1);
}
return status;
}
void ExternalSstFileIngestionJob::UpdateStats() {
// Update internal stats for new ingested files
uint64_t total_keys = 0;
uint64_t total_l0_files = 0;
uint64_t total_time = env_->NowMicros() - job_start_time_;
for (IngestedFileInfo& f : files_to_ingest_) {
InternalStats::CompactionStats stats(1);
stats.micros = total_time;
stats.bytes_written = f.fd.GetFileSize();
stats.num_output_files = 1;
cfd_->internal_stats()->AddCompactionStats(f.picked_level, stats);
cfd_->internal_stats()->AddCFStats(InternalStats::BYTES_INGESTED_ADD_FILE,
f.fd.GetFileSize());
total_keys += f.num_entries;
if (f.picked_level == 0) {
total_l0_files += 1;
}
ROCKS_LOG_INFO(
db_options_.info_log,
"[AddFile] External SST file %s was ingested in L%d with path %s "
"(global_seqno=%" PRIu64 ")\n",
f.external_file_path.c_str(), f.picked_level,
f.internal_file_path.c_str(), f.assigned_seqno);
}
cfd_->internal_stats()->AddCFStats(InternalStats::INGESTED_NUM_KEYS_TOTAL,
total_keys);
cfd_->internal_stats()->AddCFStats(InternalStats::INGESTED_NUM_FILES_TOTAL,
files_to_ingest_.size());
cfd_->internal_stats()->AddCFStats(
InternalStats::INGESTED_LEVEL0_NUM_FILES_TOTAL, total_l0_files);
}
void ExternalSstFileIngestionJob::Cleanup(const Status& status) {
if (!status.ok()) {
// We failed to add the files to the database
// remove all the files we copied
for (IngestedFileInfo& f : files_to_ingest_) {
Status s = env_->DeleteFile(f.internal_file_path);
if (!s.ok()) {
ROCKS_LOG_WARN(db_options_.info_log,
"AddFile() clean up for file %s failed : %s",
f.internal_file_path.c_str(), s.ToString().c_str());
}
}
} else if (status.ok() && ingestion_options_.move_files) {
// The files were moved and added successfully, remove original file links
for (IngestedFileInfo& f : files_to_ingest_) {
Status s = env_->DeleteFile(f.external_file_path);
if (!s.ok()) {
ROCKS_LOG_WARN(
db_options_.info_log,
"%s was added to DB successfully but failed to remove original "
"file link : %s",
f.external_file_path.c_str(), s.ToString().c_str());
}
}
}
}
Status ExternalSstFileIngestionJob::GetIngestedFileInfo(
const std::string& external_file, IngestedFileInfo* file_to_ingest) {
file_to_ingest->external_file_path = external_file;
// Get external file size
Status status = env_->GetFileSize(external_file, &file_to_ingest->file_size);
if (!status.ok()) {
return status;
}
// Create TableReader for external file
std::unique_ptr<TableReader> table_reader;
std::unique_ptr<RandomAccessFile> sst_file;
std::unique_ptr<RandomAccessFileReader> sst_file_reader;
status = env_->NewRandomAccessFile(external_file, &sst_file, env_options_);
if (!status.ok()) {
return status;
}
sst_file_reader.reset(new RandomAccessFileReader(std::move(sst_file),
external_file));
status = cfd_->ioptions()->table_factory->NewTableReader(
TableReaderOptions(*cfd_->ioptions(), env_options_,
cfd_->internal_comparator()),
std::move(sst_file_reader), file_to_ingest->file_size, &table_reader);
if (!status.ok()) {
return status;
}
// Get the external file properties
auto props = table_reader->GetTableProperties();
const auto& uprops = props->user_collected_properties;
// Get table version
auto version_iter = uprops.find(ExternalSstFilePropertyNames::kVersion);
if (version_iter == uprops.end()) {
return Status::Corruption("External file version not found");
}
file_to_ingest->version = DecodeFixed32(version_iter->second.c_str());
auto seqno_iter = uprops.find(ExternalSstFilePropertyNames::kGlobalSeqno);
if (file_to_ingest->version == 2) {
// version 2 imply that we have global sequence number
if (seqno_iter == uprops.end()) {
return Status::Corruption(
"External file global sequence number not found");
}
// Set the global sequence number
file_to_ingest->original_seqno = DecodeFixed64(seqno_iter->second.c_str());
file_to_ingest->global_seqno_offset = props->properties_offsets.at(
ExternalSstFilePropertyNames::kGlobalSeqno);
if (file_to_ingest->global_seqno_offset == 0) {
return Status::Corruption("Was not able to find file global seqno field");
}
} else if (file_to_ingest->version == 1) {
// SST file V1 should not have global seqno field
assert(seqno_iter == uprops.end());
file_to_ingest->original_seqno = 0;
if (ingestion_options_.allow_blocking_flush ||
ingestion_options_.allow_global_seqno) {
return Status::InvalidArgument(
"External SST file V1 does not support global seqno");
}
} else {
return Status::InvalidArgument("External file version is not supported");
}
// Get number of entries in table
file_to_ingest->num_entries = props->num_entries;
ParsedInternalKey key;
ReadOptions ro;
// During reading the external file we can cache blocks that we read into
// the block cache, if we later change the global seqno of this file, we will
// have block in cache that will include keys with wrong seqno.
// We need to disable fill_cache so that we read from the file without
// updating the block cache.
ro.fill_cache = false;
std::unique_ptr<InternalIterator> iter(table_reader->NewIterator(ro));
// Get first (smallest) key from file
iter->SeekToFirst();
if (!ParseInternalKey(iter->key(), &key)) {
return Status::Corruption("external file have corrupted keys");
}
if (key.sequence != 0) {
return Status::Corruption("external file have non zero sequence number");
}
file_to_ingest->smallest_user_key = key.user_key.ToString();
// Get last (largest) key from file
iter->SeekToLast();
if (!ParseInternalKey(iter->key(), &key)) {
return Status::Corruption("external file have corrupted keys");
}
if (key.sequence != 0) {
return Status::Corruption("external file have non zero sequence number");
}
file_to_ingest->largest_user_key = key.user_key.ToString();
file_to_ingest->cf_id = static_cast<uint32_t>(props->column_family_id);
file_to_ingest->table_properties = *props;
return status;
}
Status ExternalSstFileIngestionJob::AssignLevelAndSeqnoForIngestedFile(
SuperVersion* sv, bool force_global_seqno, CompactionStyle compaction_style,
IngestedFileInfo* file_to_ingest, SequenceNumber* assigned_seqno) {
Status status;
*assigned_seqno = 0;
const SequenceNumber last_seqno = versions_->LastSequence();
if (force_global_seqno) {
*assigned_seqno = last_seqno + 1;
if (compaction_style == kCompactionStyleUniversal) {
file_to_ingest->picked_level = 0;
return status;
}
}
bool overlap_with_db = false;
Arena arena;
ReadOptions ro;
ro.total_order_seek = true;
int target_level = 0;
auto* vstorage = cfd_->current()->storage_info();
for (int lvl = 0; lvl < cfd_->NumberLevels(); lvl++) {
if (lvl > 0 && lvl < vstorage->base_level()) {
continue;
}
if (vstorage->NumLevelFiles(lvl) > 0) {
bool overlap_with_level = false;
status = IngestedFileOverlapWithLevel(sv, file_to_ingest, lvl,
&overlap_with_level);
if (!status.ok()) {
return status;
}
if (overlap_with_level) {
// We must use L0 or any level higher than `lvl` to be able to overwrite
// the keys that we overlap with in this level, We also need to assign
// this file a seqno to overwrite the existing keys in level `lvl`
overlap_with_db = true;
break;
}
if (compaction_style == kCompactionStyleUniversal && lvl != 0) {
const std::vector<FileMetaData*>& level_files =
vstorage->LevelFiles(lvl);
const SequenceNumber level_largest_seqno =
(*max_element(level_files.begin(), level_files.end(),
[](FileMetaData* f1, FileMetaData* f2) {
return f1->largest_seqno < f2->largest_seqno;
}))
->largest_seqno;
// should only assign seqno to current level's largest seqno when
// the file fits
if (level_largest_seqno != 0 &&
IngestedFileFitInLevel(file_to_ingest, lvl)) {
*assigned_seqno = level_largest_seqno;
} else {
continue;
}
}
} else if (compaction_style == kCompactionStyleUniversal) {
continue;
}
// We dont overlap with any keys in this level, but we still need to check
// if our file can fit in it
if (IngestedFileFitInLevel(file_to_ingest, lvl)) {
target_level = lvl;
}
}
TEST_SYNC_POINT_CALLBACK(
"ExternalSstFileIngestionJob::AssignLevelAndSeqnoForIngestedFile",
&overlap_with_db);
file_to_ingest->picked_level = target_level;
if (overlap_with_db && *assigned_seqno == 0) {
*assigned_seqno = last_seqno + 1;
}
return status;
}
Status ExternalSstFileIngestionJob::CheckLevelForIngestedBehindFile(
IngestedFileInfo* file_to_ingest) {
auto* vstorage = cfd_->current()->storage_info();
// first check if new files fit in the bottommost level
int bottom_lvl = cfd_->NumberLevels() - 1;
if(!IngestedFileFitInLevel(file_to_ingest, bottom_lvl)) {
return Status::InvalidArgument(
"Can't ingest_behind file as it doesn't fit "
"at the bottommost level!");
}
// second check if despite allow_ingest_behind=true we still have 0 seqnums
// at some upper level
for (int lvl = 0; lvl < cfd_->NumberLevels() - 1; lvl++) {
for (auto file : vstorage->LevelFiles(lvl)) {
if (file->smallest_seqno == 0) {
return Status::InvalidArgument(
"Can't ingest_behind file as despite allow_ingest_behind=true "
"there are files with 0 seqno in database at upper levels!");
}
}
}
file_to_ingest->picked_level = bottom_lvl;
return Status::OK();
}
Status ExternalSstFileIngestionJob::AssignGlobalSeqnoForIngestedFile(
IngestedFileInfo* file_to_ingest, SequenceNumber seqno) {
if (file_to_ingest->original_seqno == seqno) {
// This file already have the correct global seqno
return Status::OK();
} else if (!ingestion_options_.allow_global_seqno) {
return Status::InvalidArgument("Global seqno is required, but disabled");
} else if (file_to_ingest->global_seqno_offset == 0) {
return Status::InvalidArgument(
"Trying to set global seqno for a file that dont have a global seqno "
"field");
}
std::unique_ptr<RandomRWFile> rwfile;
Status status = env_->NewRandomRWFile(file_to_ingest->internal_file_path,
&rwfile, env_options_);
if (!status.ok()) {
return status;
}
// Write the new seqno in the global sequence number field in the file
std::string seqno_val;
PutFixed64(&seqno_val, seqno);
status = rwfile->Write(file_to_ingest->global_seqno_offset, seqno_val);
if (status.ok()) {
file_to_ingest->assigned_seqno = seqno;
}
return status;
}
Status ExternalSstFileIngestionJob::IngestedFileOverlapWithIteratorRange(
const IngestedFileInfo* file_to_ingest, InternalIterator* iter,
bool* overlap) {
auto* vstorage = cfd_->current()->storage_info();
auto* ucmp = vstorage->InternalComparator()->user_comparator();
InternalKey range_start(file_to_ingest->smallest_user_key, kMaxSequenceNumber,
kValueTypeForSeek);
iter->Seek(range_start.Encode());
if (!iter->status().ok()) {
return iter->status();
}
*overlap = false;
if (iter->Valid()) {
ParsedInternalKey seek_result;
if (!ParseInternalKey(iter->key(), &seek_result)) {
return Status::Corruption("DB have corrupted keys");
}
if (ucmp->Compare(seek_result.user_key, file_to_ingest->largest_user_key) <=
0) {
*overlap = true;
}
}
return iter->status();
}
bool ExternalSstFileIngestionJob::IngestedFileFitInLevel(
const IngestedFileInfo* file_to_ingest, int level) {
if (level == 0) {
// Files can always fit in L0
return true;
}
auto* vstorage = cfd_->current()->storage_info();
Slice file_smallest_user_key(file_to_ingest->smallest_user_key);
Slice file_largest_user_key(file_to_ingest->largest_user_key);
if (vstorage->OverlapInLevel(level, &file_smallest_user_key,
&file_largest_user_key)) {
// File overlap with another files in this level, we cannot
// add it to this level
return false;
}
if (cfd_->RangeOverlapWithCompaction(file_smallest_user_key,
file_largest_user_key, level)) {
// File overlap with a running compaction output that will be stored
// in this level, we cannot add this file to this level
return false;
}
// File did not overlap with level files, our compaction output
return true;
}
Status ExternalSstFileIngestionJob::IngestedFileOverlapWithLevel(
SuperVersion* sv, IngestedFileInfo* file_to_ingest, int lvl,
bool* overlap_with_level) {
Arena arena;
ReadOptions ro;
ro.total_order_seek = true;
MergeIteratorBuilder merge_iter_builder(&cfd_->internal_comparator(),
&arena);
// Files are opened lazily when the iterator needs them, thus range deletions
// are also added lazily to the aggregator. We need to check for range
// deletion overlap only in the case where there's no point-key overlap. Then,
// we've already opened the file with range containing the ingested file's
// begin key, and iterated through all files until the one containing the
// ingested file's end key. So any files maybe containing range deletions
// overlapping the ingested file must have been opened and had their range
// deletions added to the aggregator.
RangeDelAggregator range_del_agg(cfd_->internal_comparator(),
{} /* snapshots */,
false /* collapse_deletions */);
sv->current->AddIteratorsForLevel(ro, env_options_, &merge_iter_builder, lvl,
&range_del_agg);
ScopedArenaIterator level_iter(merge_iter_builder.Finish());
Status status = IngestedFileOverlapWithIteratorRange(
file_to_ingest, level_iter.get(), overlap_with_level);
if (status.ok() && *overlap_with_level == false &&
range_del_agg.IsRangeOverlapped(file_to_ingest->smallest_user_key,
file_to_ingest->largest_user_key)) {
*overlap_with_level = true;
}
return status;
}
} // namespace rocksdb
#endif // !ROCKSDB_LITE