rocksdb/options/options.cc
Yi Wu 07bdcb91fe New WriteImpl to pipeline WAL/memtable write
Summary:
PipelineWriteImpl is an alternative approach to WriteImpl. In WriteImpl, only one thread is allow to write at the same time. This thread will do both WAL and memtable writes for all write threads in the write group. Pending writers wait in queue until the current writer finishes. In the pipeline write approach, two queue is maintained: one WAL writer queue and one memtable writer queue. All writers (regardless of whether they need to write WAL) will still need to first join the WAL writer queue, and after the house keeping work and WAL writing, they will need to join memtable writer queue if needed. The benefit of this approach is that
1. Writers without memtable writes (e.g. the prepare phase of two phase commit) can exit write thread once WAL write is finish. They don't need to wait for memtable writes in case of group commit.
2. Pending writers only need to wait for previous WAL writer finish to be able to join the write thread, instead of wait also for previous memtable writes.

Merging #2056 and #2058 into this PR.
Closes https://github.com/facebook/rocksdb/pull/2286

Differential Revision: D5054606

Pulled By: yiwu-arbug

fbshipit-source-id: ee5b11efd19d3e39d6b7210937b11cefdd4d1c8d
2017-05-19 14:26:42 -07:00

636 lines
27 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
// This source code is also licensed under the GPLv2 license found in the
// COPYING file in the root directory of this source tree.
//
// 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 "rocksdb/options.h"
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
#include <limits>
#include "monitoring/statistics.h"
#include "options/db_options.h"
#include "options/options_helper.h"
#include "rocksdb/cache.h"
#include "rocksdb/compaction_filter.h"
#include "rocksdb/comparator.h"
#include "rocksdb/env.h"
#include "rocksdb/memtablerep.h"
#include "rocksdb/merge_operator.h"
#include "rocksdb/slice.h"
#include "rocksdb/slice_transform.h"
#include "rocksdb/sst_file_manager.h"
#include "rocksdb/table.h"
#include "rocksdb/table_properties.h"
#include "rocksdb/wal_filter.h"
#include "table/block_based_table_factory.h"
#include "util/compression.h"
namespace rocksdb {
AdvancedColumnFamilyOptions::AdvancedColumnFamilyOptions() {
assert(memtable_factory.get() != nullptr);
}
AdvancedColumnFamilyOptions::AdvancedColumnFamilyOptions(const Options& options)
: max_write_buffer_number(options.max_write_buffer_number),
min_write_buffer_number_to_merge(
options.min_write_buffer_number_to_merge),
max_write_buffer_number_to_maintain(
options.max_write_buffer_number_to_maintain),
inplace_update_support(options.inplace_update_support),
inplace_update_num_locks(options.inplace_update_num_locks),
inplace_callback(options.inplace_callback),
memtable_prefix_bloom_size_ratio(
options.memtable_prefix_bloom_size_ratio),
memtable_huge_page_size(options.memtable_huge_page_size),
memtable_insert_with_hint_prefix_extractor(
options.memtable_insert_with_hint_prefix_extractor),
bloom_locality(options.bloom_locality),
arena_block_size(options.arena_block_size),
compression_per_level(options.compression_per_level),
num_levels(options.num_levels),
level0_slowdown_writes_trigger(options.level0_slowdown_writes_trigger),
level0_stop_writes_trigger(options.level0_stop_writes_trigger),
target_file_size_base(options.target_file_size_base),
target_file_size_multiplier(options.target_file_size_multiplier),
level_compaction_dynamic_level_bytes(
options.level_compaction_dynamic_level_bytes),
max_bytes_for_level_multiplier(options.max_bytes_for_level_multiplier),
max_bytes_for_level_multiplier_additional(
options.max_bytes_for_level_multiplier_additional),
max_compaction_bytes(options.max_compaction_bytes),
soft_pending_compaction_bytes_limit(
options.soft_pending_compaction_bytes_limit),
hard_pending_compaction_bytes_limit(
options.hard_pending_compaction_bytes_limit),
compaction_style(options.compaction_style),
compaction_pri(options.compaction_pri),
compaction_options_universal(options.compaction_options_universal),
compaction_options_fifo(options.compaction_options_fifo),
max_sequential_skip_in_iterations(
options.max_sequential_skip_in_iterations),
memtable_factory(options.memtable_factory),
table_properties_collector_factories(
options.table_properties_collector_factories),
max_successive_merges(options.max_successive_merges),
optimize_filters_for_hits(options.optimize_filters_for_hits),
paranoid_file_checks(options.paranoid_file_checks),
force_consistency_checks(options.force_consistency_checks),
report_bg_io_stats(options.report_bg_io_stats) {
assert(memtable_factory.get() != nullptr);
if (max_bytes_for_level_multiplier_additional.size() <
static_cast<unsigned int>(num_levels)) {
max_bytes_for_level_multiplier_additional.resize(num_levels, 1);
}
}
ColumnFamilyOptions::ColumnFamilyOptions()
: compression(Snappy_Supported() ? kSnappyCompression : kNoCompression),
table_factory(
std::shared_ptr<TableFactory>(new BlockBasedTableFactory())) {}
ColumnFamilyOptions::ColumnFamilyOptions(const Options& options)
: AdvancedColumnFamilyOptions(options),
comparator(options.comparator),
merge_operator(options.merge_operator),
compaction_filter(options.compaction_filter),
compaction_filter_factory(options.compaction_filter_factory),
write_buffer_size(options.write_buffer_size),
compression(options.compression),
bottommost_compression(options.bottommost_compression),
compression_opts(options.compression_opts),
level0_file_num_compaction_trigger(
options.level0_file_num_compaction_trigger),
prefix_extractor(options.prefix_extractor),
max_bytes_for_level_base(options.max_bytes_for_level_base),
disable_auto_compactions(options.disable_auto_compactions),
table_factory(options.table_factory) {}
DBOptions::DBOptions() {}
DBOptions::DBOptions(const Options& options)
: create_if_missing(options.create_if_missing),
create_missing_column_families(options.create_missing_column_families),
error_if_exists(options.error_if_exists),
paranoid_checks(options.paranoid_checks),
env(options.env),
rate_limiter(options.rate_limiter),
sst_file_manager(options.sst_file_manager),
info_log(options.info_log),
info_log_level(options.info_log_level),
max_open_files(options.max_open_files),
max_file_opening_threads(options.max_file_opening_threads),
max_total_wal_size(options.max_total_wal_size),
statistics(options.statistics),
use_fsync(options.use_fsync),
db_paths(options.db_paths),
db_log_dir(options.db_log_dir),
wal_dir(options.wal_dir),
delete_obsolete_files_period_micros(
options.delete_obsolete_files_period_micros),
base_background_compactions(options.base_background_compactions),
max_background_compactions(options.max_background_compactions),
max_subcompactions(options.max_subcompactions),
max_background_flushes(options.max_background_flushes),
max_log_file_size(options.max_log_file_size),
log_file_time_to_roll(options.log_file_time_to_roll),
keep_log_file_num(options.keep_log_file_num),
recycle_log_file_num(options.recycle_log_file_num),
max_manifest_file_size(options.max_manifest_file_size),
table_cache_numshardbits(options.table_cache_numshardbits),
WAL_ttl_seconds(options.WAL_ttl_seconds),
WAL_size_limit_MB(options.WAL_size_limit_MB),
manifest_preallocation_size(options.manifest_preallocation_size),
allow_mmap_reads(options.allow_mmap_reads),
allow_mmap_writes(options.allow_mmap_writes),
use_direct_reads(options.use_direct_reads),
use_direct_io_for_flush_and_compaction(
options.use_direct_io_for_flush_and_compaction),
allow_fallocate(options.allow_fallocate),
is_fd_close_on_exec(options.is_fd_close_on_exec),
skip_log_error_on_recovery(options.skip_log_error_on_recovery),
stats_dump_period_sec(options.stats_dump_period_sec),
advise_random_on_open(options.advise_random_on_open),
db_write_buffer_size(options.db_write_buffer_size),
write_buffer_manager(options.write_buffer_manager),
access_hint_on_compaction_start(options.access_hint_on_compaction_start),
new_table_reader_for_compaction_inputs(
options.new_table_reader_for_compaction_inputs),
compaction_readahead_size(options.compaction_readahead_size),
random_access_max_buffer_size(options.random_access_max_buffer_size),
writable_file_max_buffer_size(options.writable_file_max_buffer_size),
use_adaptive_mutex(options.use_adaptive_mutex),
bytes_per_sync(options.bytes_per_sync),
wal_bytes_per_sync(options.wal_bytes_per_sync),
listeners(options.listeners),
enable_thread_tracking(options.enable_thread_tracking),
delayed_write_rate(options.delayed_write_rate),
enable_pipelined_write(options.enable_pipelined_write),
allow_concurrent_memtable_write(options.allow_concurrent_memtable_write),
enable_write_thread_adaptive_yield(
options.enable_write_thread_adaptive_yield),
write_thread_max_yield_usec(options.write_thread_max_yield_usec),
write_thread_slow_yield_usec(options.write_thread_slow_yield_usec),
skip_stats_update_on_db_open(options.skip_stats_update_on_db_open),
wal_recovery_mode(options.wal_recovery_mode),
row_cache(options.row_cache),
#ifndef ROCKSDB_LITE
wal_filter(options.wal_filter),
#endif // ROCKSDB_LITE
fail_if_options_file_error(options.fail_if_options_file_error),
dump_malloc_stats(options.dump_malloc_stats),
avoid_flush_during_recovery(options.avoid_flush_during_recovery),
avoid_flush_during_shutdown(options.avoid_flush_during_shutdown),
allow_ingest_behind(options.allow_ingest_behind) {
}
void DBOptions::Dump(Logger* log) const {
ImmutableDBOptions(*this).Dump(log);
MutableDBOptions(*this).Dump(log);
} // DBOptions::Dump
void ColumnFamilyOptions::Dump(Logger* log) const {
ROCKS_LOG_HEADER(log, " Options.comparator: %s",
comparator->Name());
ROCKS_LOG_HEADER(log, " Options.merge_operator: %s",
merge_operator ? merge_operator->Name() : "None");
ROCKS_LOG_HEADER(log, " Options.compaction_filter: %s",
compaction_filter ? compaction_filter->Name() : "None");
ROCKS_LOG_HEADER(
log, " Options.compaction_filter_factory: %s",
compaction_filter_factory ? compaction_filter_factory->Name() : "None");
ROCKS_LOG_HEADER(log, " Options.memtable_factory: %s",
memtable_factory->Name());
ROCKS_LOG_HEADER(log, " Options.table_factory: %s",
table_factory->Name());
ROCKS_LOG_HEADER(log, " table_factory options: %s",
table_factory->GetPrintableTableOptions().c_str());
ROCKS_LOG_HEADER(log, " Options.write_buffer_size: %" ROCKSDB_PRIszt,
write_buffer_size);
ROCKS_LOG_HEADER(log, " Options.max_write_buffer_number: %d",
max_write_buffer_number);
if (!compression_per_level.empty()) {
for (unsigned int i = 0; i < compression_per_level.size(); i++) {
ROCKS_LOG_HEADER(
log, " Options.compression[%d]: %s", i,
CompressionTypeToString(compression_per_level[i]).c_str());
}
} else {
ROCKS_LOG_HEADER(log, " Options.compression: %s",
CompressionTypeToString(compression).c_str());
}
ROCKS_LOG_HEADER(
log, " Options.bottommost_compression: %s",
bottommost_compression == kDisableCompressionOption
? "Disabled"
: CompressionTypeToString(bottommost_compression).c_str());
ROCKS_LOG_HEADER(
log, " Options.prefix_extractor: %s",
prefix_extractor == nullptr ? "nullptr" : prefix_extractor->Name());
ROCKS_LOG_HEADER(log,
" Options.memtable_insert_with_hint_prefix_extractor: %s",
memtable_insert_with_hint_prefix_extractor == nullptr
? "nullptr"
: memtable_insert_with_hint_prefix_extractor->Name());
ROCKS_LOG_HEADER(log, " Options.num_levels: %d", num_levels);
ROCKS_LOG_HEADER(log, " Options.min_write_buffer_number_to_merge: %d",
min_write_buffer_number_to_merge);
ROCKS_LOG_HEADER(log, " Options.max_write_buffer_number_to_maintain: %d",
max_write_buffer_number_to_maintain);
ROCKS_LOG_HEADER(log, " Options.compression_opts.window_bits: %d",
compression_opts.window_bits);
ROCKS_LOG_HEADER(log, " Options.compression_opts.level: %d",
compression_opts.level);
ROCKS_LOG_HEADER(log, " Options.compression_opts.strategy: %d",
compression_opts.strategy);
ROCKS_LOG_HEADER(
log,
" Options.compression_opts.max_dict_bytes: %" ROCKSDB_PRIszt,
compression_opts.max_dict_bytes);
ROCKS_LOG_HEADER(log, " Options.level0_file_num_compaction_trigger: %d",
level0_file_num_compaction_trigger);
ROCKS_LOG_HEADER(log, " Options.level0_slowdown_writes_trigger: %d",
level0_slowdown_writes_trigger);
ROCKS_LOG_HEADER(log, " Options.level0_stop_writes_trigger: %d",
level0_stop_writes_trigger);
ROCKS_LOG_HEADER(
log, " Options.target_file_size_base: %" PRIu64,
target_file_size_base);
ROCKS_LOG_HEADER(log, " Options.target_file_size_multiplier: %d",
target_file_size_multiplier);
ROCKS_LOG_HEADER(
log, " Options.max_bytes_for_level_base: %" PRIu64,
max_bytes_for_level_base);
ROCKS_LOG_HEADER(log, "Options.level_compaction_dynamic_level_bytes: %d",
level_compaction_dynamic_level_bytes);
ROCKS_LOG_HEADER(log, " Options.max_bytes_for_level_multiplier: %f",
max_bytes_for_level_multiplier);
for (size_t i = 0; i < max_bytes_for_level_multiplier_additional.size();
i++) {
ROCKS_LOG_HEADER(
log, "Options.max_bytes_for_level_multiplier_addtl[%" ROCKSDB_PRIszt
"]: %d",
i, max_bytes_for_level_multiplier_additional[i]);
}
ROCKS_LOG_HEADER(
log, " Options.max_sequential_skip_in_iterations: %" PRIu64,
max_sequential_skip_in_iterations);
ROCKS_LOG_HEADER(
log, " Options.max_compaction_bytes: %" PRIu64,
max_compaction_bytes);
ROCKS_LOG_HEADER(
log,
" Options.arena_block_size: %" ROCKSDB_PRIszt,
arena_block_size);
ROCKS_LOG_HEADER(log,
" Options.soft_pending_compaction_bytes_limit: %" PRIu64,
soft_pending_compaction_bytes_limit);
ROCKS_LOG_HEADER(log,
" Options.hard_pending_compaction_bytes_limit: %" PRIu64,
hard_pending_compaction_bytes_limit);
ROCKS_LOG_HEADER(log, " Options.rate_limit_delay_max_milliseconds: %u",
rate_limit_delay_max_milliseconds);
ROCKS_LOG_HEADER(log, " Options.disable_auto_compactions: %d",
disable_auto_compactions);
const auto& it_compaction_style =
compaction_style_to_string.find(compaction_style);
std::string str_compaction_style;
if (it_compaction_style == compaction_style_to_string.end()) {
assert(false);
str_compaction_style = "unknown_" + std::to_string(compaction_style);
} else {
str_compaction_style = it_compaction_style->second;
}
ROCKS_LOG_HEADER(log,
" Options.compaction_style: %s",
str_compaction_style.c_str());
const auto& it_compaction_pri =
compaction_pri_to_string.find(compaction_pri);
std::string str_compaction_pri;
if (it_compaction_pri == compaction_pri_to_string.end()) {
assert(false);
str_compaction_pri = "unknown_" + std::to_string(compaction_pri);
} else {
str_compaction_pri = it_compaction_pri->second;
}
ROCKS_LOG_HEADER(log,
" Options.compaction_pri: %s",
str_compaction_pri.c_str());
ROCKS_LOG_HEADER(log,
"Options.compaction_options_universal.size_ratio: %u",
compaction_options_universal.size_ratio);
ROCKS_LOG_HEADER(log,
"Options.compaction_options_universal.min_merge_width: %u",
compaction_options_universal.min_merge_width);
ROCKS_LOG_HEADER(log,
"Options.compaction_options_universal.max_merge_width: %u",
compaction_options_universal.max_merge_width);
ROCKS_LOG_HEADER(
log,
"Options.compaction_options_universal."
"max_size_amplification_percent: %u",
compaction_options_universal.max_size_amplification_percent);
ROCKS_LOG_HEADER(
log,
"Options.compaction_options_universal.compression_size_percent: %d",
compaction_options_universal.compression_size_percent);
const auto& it_compaction_stop_style = compaction_stop_style_to_string.find(
compaction_options_universal.stop_style);
std::string str_compaction_stop_style;
if (it_compaction_stop_style == compaction_stop_style_to_string.end()) {
assert(false);
str_compaction_stop_style =
"unknown_" + std::to_string(compaction_options_universal.stop_style);
} else {
str_compaction_stop_style = it_compaction_stop_style->second;
}
ROCKS_LOG_HEADER(log,
"Options.compaction_options_universal.stop_style: %s",
str_compaction_stop_style.c_str());
ROCKS_LOG_HEADER(
log, "Options.compaction_options_fifo.max_table_files_size: %" PRIu64,
compaction_options_fifo.max_table_files_size);
ROCKS_LOG_HEADER(log,
"Options.compaction_options_fifo.allow_compaction: %d",
compaction_options_fifo.allow_compaction);
std::string collector_names;
for (const auto& collector_factory : table_properties_collector_factories) {
collector_names.append(collector_factory->Name());
collector_names.append("; ");
}
ROCKS_LOG_HEADER(
log, " Options.table_properties_collectors: %s",
collector_names.c_str());
ROCKS_LOG_HEADER(log,
" Options.inplace_update_support: %d",
inplace_update_support);
ROCKS_LOG_HEADER(
log,
" Options.inplace_update_num_locks: %" ROCKSDB_PRIszt,
inplace_update_num_locks);
// TODO: easier config for bloom (maybe based on avg key/value size)
ROCKS_LOG_HEADER(
log, " Options.memtable_prefix_bloom_size_ratio: %f",
memtable_prefix_bloom_size_ratio);
ROCKS_LOG_HEADER(log, " Options.memtable_huge_page_size: %" ROCKSDB_PRIszt,
memtable_huge_page_size);
ROCKS_LOG_HEADER(log,
" Options.bloom_locality: %d",
bloom_locality);
ROCKS_LOG_HEADER(
log,
" Options.max_successive_merges: %" ROCKSDB_PRIszt,
max_successive_merges);
ROCKS_LOG_HEADER(log,
" Options.optimize_filters_for_hits: %d",
optimize_filters_for_hits);
ROCKS_LOG_HEADER(log, " Options.paranoid_file_checks: %d",
paranoid_file_checks);
ROCKS_LOG_HEADER(log, " Options.force_consistency_checks: %d",
force_consistency_checks);
ROCKS_LOG_HEADER(log, " Options.report_bg_io_stats: %d",
report_bg_io_stats);
} // ColumnFamilyOptions::Dump
void Options::Dump(Logger* log) const {
DBOptions::Dump(log);
ColumnFamilyOptions::Dump(log);
} // Options::Dump
void Options::DumpCFOptions(Logger* log) const {
ColumnFamilyOptions::Dump(log);
} // Options::DumpCFOptions
//
// The goal of this method is to create a configuration that
// allows an application to write all files into L0 and
// then do a single compaction to output all files into L1.
Options*
Options::PrepareForBulkLoad()
{
// never slowdown ingest.
level0_file_num_compaction_trigger = (1<<30);
level0_slowdown_writes_trigger = (1<<30);
level0_stop_writes_trigger = (1<<30);
soft_pending_compaction_bytes_limit = 0;
hard_pending_compaction_bytes_limit = 0;
// no auto compactions please. The application should issue a
// manual compaction after all data is loaded into L0.
disable_auto_compactions = true;
// A manual compaction run should pick all files in L0 in
// a single compaction run.
max_compaction_bytes = (static_cast<uint64_t>(1) << 60);
// It is better to have only 2 levels, otherwise a manual
// compaction would compact at every possible level, thereby
// increasing the total time needed for compactions.
num_levels = 2;
// Need to allow more write buffers to allow more parallism
// of flushes.
max_write_buffer_number = 6;
min_write_buffer_number_to_merge = 1;
// When compaction is disabled, more parallel flush threads can
// help with write throughput.
max_background_flushes = 4;
// Prevent a memtable flush to automatically promote files
// to L1. This is helpful so that all files that are
// input to the manual compaction are all at L0.
max_background_compactions = 2;
base_background_compactions = 2;
// The compaction would create large files in L1.
target_file_size_base = 256 * 1024 * 1024;
return this;
}
Options* Options::OptimizeForSmallDb() {
ColumnFamilyOptions::OptimizeForSmallDb();
DBOptions::OptimizeForSmallDb();
return this;
}
Options* Options::OldDefaults(int rocksdb_major_version,
int rocksdb_minor_version) {
ColumnFamilyOptions::OldDefaults(rocksdb_major_version,
rocksdb_minor_version);
DBOptions::OldDefaults(rocksdb_major_version, rocksdb_minor_version);
return this;
}
DBOptions* DBOptions::OldDefaults(int rocksdb_major_version,
int rocksdb_minor_version) {
if (rocksdb_major_version < 4 ||
(rocksdb_major_version == 4 && rocksdb_minor_version < 7)) {
max_file_opening_threads = 1;
table_cache_numshardbits = 4;
}
if (rocksdb_major_version < 5 ||
(rocksdb_major_version == 5 && rocksdb_minor_version < 2)) {
delayed_write_rate = 2 * 1024U * 1024U;
}
max_open_files = 5000;
base_background_compactions = -1;
wal_recovery_mode = WALRecoveryMode::kTolerateCorruptedTailRecords;
return this;
}
ColumnFamilyOptions* ColumnFamilyOptions::OldDefaults(
int rocksdb_major_version, int rocksdb_minor_version) {
if (rocksdb_major_version < 4 ||
(rocksdb_major_version == 4 && rocksdb_minor_version < 7)) {
write_buffer_size = 4 << 20;
target_file_size_base = 2 * 1048576;
max_bytes_for_level_base = 10 * 1048576;
soft_pending_compaction_bytes_limit = 0;
hard_pending_compaction_bytes_limit = 0;
}
if (rocksdb_major_version < 5) {
level0_stop_writes_trigger = 24;
} else if (rocksdb_major_version == 5 && rocksdb_minor_version < 2) {
level0_stop_writes_trigger = 30;
}
compaction_pri = CompactionPri::kByCompensatedSize;
return this;
}
// Optimization functions
DBOptions* DBOptions::OptimizeForSmallDb() {
max_file_opening_threads = 1;
max_open_files = 5000;
return this;
}
ColumnFamilyOptions* ColumnFamilyOptions::OptimizeForSmallDb() {
write_buffer_size = 2 << 20;
target_file_size_base = 2 * 1048576;
max_bytes_for_level_base = 10 * 1048576;
soft_pending_compaction_bytes_limit = 256 * 1048576;
hard_pending_compaction_bytes_limit = 1073741824ul;
return this;
}
#ifndef ROCKSDB_LITE
ColumnFamilyOptions* ColumnFamilyOptions::OptimizeForPointLookup(
uint64_t block_cache_size_mb) {
prefix_extractor.reset(NewNoopTransform());
BlockBasedTableOptions block_based_options;
block_based_options.index_type = BlockBasedTableOptions::kHashSearch;
block_based_options.filter_policy.reset(NewBloomFilterPolicy(10));
block_based_options.block_cache =
NewLRUCache(static_cast<size_t>(block_cache_size_mb * 1024 * 1024));
table_factory.reset(new BlockBasedTableFactory(block_based_options));
memtable_prefix_bloom_size_ratio = 0.02;
return this;
}
ColumnFamilyOptions* ColumnFamilyOptions::OptimizeLevelStyleCompaction(
uint64_t memtable_memory_budget) {
write_buffer_size = static_cast<size_t>(memtable_memory_budget / 4);
// merge two memtables when flushing to L0
min_write_buffer_number_to_merge = 2;
// this means we'll use 50% extra memory in the worst case, but will reduce
// write stalls.
max_write_buffer_number = 6;
// start flushing L0->L1 as soon as possible. each file on level0 is
// (memtable_memory_budget / 2). This will flush level 0 when it's bigger than
// memtable_memory_budget.
level0_file_num_compaction_trigger = 2;
// doesn't really matter much, but we don't want to create too many files
target_file_size_base = memtable_memory_budget / 8;
// make Level1 size equal to Level0 size, so that L0->L1 compactions are fast
max_bytes_for_level_base = memtable_memory_budget;
// level style compaction
compaction_style = kCompactionStyleLevel;
// only compress levels >= 2
compression_per_level.resize(num_levels);
for (int i = 0; i < num_levels; ++i) {
if (i < 2) {
compression_per_level[i] = kNoCompression;
} else {
compression_per_level[i] = kSnappyCompression;
}
}
return this;
}
ColumnFamilyOptions* ColumnFamilyOptions::OptimizeUniversalStyleCompaction(
uint64_t memtable_memory_budget) {
write_buffer_size = static_cast<size_t>(memtable_memory_budget / 4);
// merge two memtables when flushing to L0
min_write_buffer_number_to_merge = 2;
// this means we'll use 50% extra memory in the worst case, but will reduce
// write stalls.
max_write_buffer_number = 6;
// universal style compaction
compaction_style = kCompactionStyleUniversal;
compaction_options_universal.compression_size_percent = 80;
return this;
}
DBOptions* DBOptions::IncreaseParallelism(int total_threads) {
max_background_compactions = total_threads - 1;
max_background_flushes = 1;
env->SetBackgroundThreads(total_threads, Env::LOW);
env->SetBackgroundThreads(1, Env::HIGH);
return this;
}
#endif // !ROCKSDB_LITE
ReadOptions::ReadOptions()
: verify_checksums(true),
fill_cache(true),
snapshot(nullptr),
iterate_upper_bound(nullptr),
read_tier(kReadAllTier),
tailing(false),
managed(false),
total_order_seek(false),
prefix_same_as_start(false),
pin_data(false),
background_purge_on_iterator_cleanup(false),
readahead_size(0),
ignore_range_deletions(false),
max_skippable_internal_keys(0) {}
ReadOptions::ReadOptions(bool cksum, bool cache)
: verify_checksums(cksum),
fill_cache(cache),
snapshot(nullptr),
iterate_upper_bound(nullptr),
read_tier(kReadAllTier),
tailing(false),
managed(false),
total_order_seek(false),
prefix_same_as_start(false),
pin_data(false),
background_purge_on_iterator_cleanup(false),
readahead_size(0),
ignore_range_deletions(false),
max_skippable_internal_keys(0) {}
} // namespace rocksdb