rocksdb/util/options.cc
Sameet Agarwal e7c434c364 Add columnfamily option optimize_filters_for_hits to optimize for key hits only
Summary:
    Summary:
    Added a new option to ColumnFamllyOptions  - optimize_filters_for_hits. This option can be used in the case where most
    accesses to the store are key hits and we dont need to optimize performance for key misses.
    This is useful when you have a very large database and most of your lookups succeed.  The option allows the store to
     not store and use filters in the last level (the largest level which contains data). These filters can take a large amount of
     space for large databases (in memory and on-disk). For the last level, these filters are only useful for key misses and not
     for key hits. If we are not optimizing for key misses, we can choose to not store these filters for that level.

    This option is only provided for BlockBasedTable. We skip the filters when we are compacting

Test Plan:
1. Modified db_test toalso run tests with an additonal option (skip_filters_on_last_level)
 2. Added another unit test to db_test which specifically tests that filters are being skipped

Reviewers: rven, igor, sdong

Reviewed By: sdong

Subscribers: lgalanis, yoshinorim, MarkCallaghan, rven, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D33717
2015-02-26 16:25:56 -08:00

636 lines
27 KiB
C++

// Copyright (c) 2013, 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.
//
// 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"
#include "rocksdb/immutable_options.h"
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
#include <limits>
#include "db/writebuffer.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/table.h"
#include "rocksdb/table_properties.h"
#include "table/block_based_table_factory.h"
#include "util/statistics.h"
#include "util/xfunc.h"
namespace rocksdb {
ImmutableCFOptions::ImmutableCFOptions(const Options& options)
: compaction_style(options.compaction_style),
compaction_options_universal(options.compaction_options_universal),
compaction_options_fifo(options.compaction_options_fifo),
prefix_extractor(options.prefix_extractor.get()),
comparator(options.comparator),
merge_operator(options.merge_operator.get()),
compaction_filter(options.compaction_filter),
compaction_filter_factory(options.compaction_filter_factory.get()),
compaction_filter_factory_v2(options.compaction_filter_factory_v2.get()),
inplace_update_support(options.inplace_update_support),
inplace_callback(options.inplace_callback),
info_log(options.info_log.get()),
statistics(options.statistics.get()),
env(options.env),
allow_mmap_reads(options.allow_mmap_reads),
allow_mmap_writes(options.allow_mmap_writes),
db_paths(options.db_paths),
memtable_factory(options.memtable_factory.get()),
table_factory(options.table_factory.get()),
table_properties_collector_factories(
options.table_properties_collector_factories),
advise_random_on_open(options.advise_random_on_open),
bloom_locality(options.bloom_locality),
purge_redundant_kvs_while_flush(options.purge_redundant_kvs_while_flush),
min_partial_merge_operands(options.min_partial_merge_operands),
disable_data_sync(options.disableDataSync),
use_fsync(options.use_fsync),
compression(options.compression),
compression_per_level(options.compression_per_level),
compression_opts(options.compression_opts),
access_hint_on_compaction_start(options.access_hint_on_compaction_start),
num_levels(options.num_levels),
optimize_filters_for_hits(options.optimize_filters_for_hits)
#ifndef ROCKSDB_LITE
, listeners(options.listeners) {}
#else // ROCKSDB_LITE
{}
#endif // ROCKSDB_LITE
ColumnFamilyOptions::ColumnFamilyOptions()
: comparator(BytewiseComparator()),
merge_operator(nullptr),
compaction_filter(nullptr),
compaction_filter_factory(std::shared_ptr<CompactionFilterFactory>(
new DefaultCompactionFilterFactory())),
compaction_filter_factory_v2(new DefaultCompactionFilterFactoryV2()),
write_buffer_size(4 << 20),
max_write_buffer_number(2),
min_write_buffer_number_to_merge(1),
compression(kSnappyCompression),
prefix_extractor(nullptr),
num_levels(7),
level0_file_num_compaction_trigger(4),
level0_slowdown_writes_trigger(20),
level0_stop_writes_trigger(24),
max_mem_compaction_level(2),
target_file_size_base(2 * 1048576),
target_file_size_multiplier(1),
max_bytes_for_level_base(10 * 1048576),
max_bytes_for_level_multiplier(10),
max_bytes_for_level_multiplier_additional(num_levels, 1),
expanded_compaction_factor(25),
source_compaction_factor(1),
max_grandparent_overlap_factor(10),
soft_rate_limit(0.0),
hard_rate_limit(0.0),
rate_limit_delay_max_milliseconds(1000),
arena_block_size(0),
disable_auto_compactions(false),
purge_redundant_kvs_while_flush(true),
compaction_style(kCompactionStyleLevel),
verify_checksums_in_compaction(true),
filter_deletes(false),
max_sequential_skip_in_iterations(8),
memtable_factory(std::shared_ptr<SkipListFactory>(new SkipListFactory)),
table_factory(
std::shared_ptr<TableFactory>(new BlockBasedTableFactory())),
inplace_update_support(false),
inplace_update_num_locks(10000),
inplace_callback(nullptr),
memtable_prefix_bloom_bits(0),
memtable_prefix_bloom_probes(6),
memtable_prefix_bloom_huge_page_tlb_size(0),
bloom_locality(0),
max_successive_merges(0),
min_partial_merge_operands(2),
optimize_filters_for_hits(false)
#ifndef ROCKSDB_LITE
, listeners() {
#else // ROCKSDB_LITE
{
#endif // ROCKSDB_LITE
assert(memtable_factory.get() != nullptr);
}
ColumnFamilyOptions::ColumnFamilyOptions(const Options& options)
: comparator(options.comparator),
merge_operator(options.merge_operator),
compaction_filter(options.compaction_filter),
compaction_filter_factory(options.compaction_filter_factory),
compaction_filter_factory_v2(options.compaction_filter_factory_v2),
write_buffer_size(options.write_buffer_size),
max_write_buffer_number(options.max_write_buffer_number),
min_write_buffer_number_to_merge(
options.min_write_buffer_number_to_merge),
compression(options.compression),
compression_per_level(options.compression_per_level),
compression_opts(options.compression_opts),
prefix_extractor(options.prefix_extractor),
num_levels(options.num_levels),
level0_file_num_compaction_trigger(
options.level0_file_num_compaction_trigger),
level0_slowdown_writes_trigger(options.level0_slowdown_writes_trigger),
level0_stop_writes_trigger(options.level0_stop_writes_trigger),
max_mem_compaction_level(options.max_mem_compaction_level),
target_file_size_base(options.target_file_size_base),
target_file_size_multiplier(options.target_file_size_multiplier),
max_bytes_for_level_base(options.max_bytes_for_level_base),
max_bytes_for_level_multiplier(options.max_bytes_for_level_multiplier),
max_bytes_for_level_multiplier_additional(
options.max_bytes_for_level_multiplier_additional),
expanded_compaction_factor(options.expanded_compaction_factor),
source_compaction_factor(options.source_compaction_factor),
max_grandparent_overlap_factor(options.max_grandparent_overlap_factor),
soft_rate_limit(options.soft_rate_limit),
hard_rate_limit(options.hard_rate_limit),
rate_limit_delay_max_milliseconds(
options.rate_limit_delay_max_milliseconds),
arena_block_size(options.arena_block_size),
disable_auto_compactions(options.disable_auto_compactions),
purge_redundant_kvs_while_flush(options.purge_redundant_kvs_while_flush),
compaction_style(options.compaction_style),
verify_checksums_in_compaction(options.verify_checksums_in_compaction),
compaction_options_universal(options.compaction_options_universal),
compaction_options_fifo(options.compaction_options_fifo),
filter_deletes(options.filter_deletes),
max_sequential_skip_in_iterations(
options.max_sequential_skip_in_iterations),
memtable_factory(options.memtable_factory),
table_factory(options.table_factory),
table_properties_collector_factories(
options.table_properties_collector_factories),
inplace_update_support(options.inplace_update_support),
inplace_update_num_locks(options.inplace_update_num_locks),
inplace_callback(options.inplace_callback),
memtable_prefix_bloom_bits(options.memtable_prefix_bloom_bits),
memtable_prefix_bloom_probes(options.memtable_prefix_bloom_probes),
memtable_prefix_bloom_huge_page_tlb_size(
options.memtable_prefix_bloom_huge_page_tlb_size),
bloom_locality(options.bloom_locality),
max_successive_merges(options.max_successive_merges),
min_partial_merge_operands(options.min_partial_merge_operands),
optimize_filters_for_hits(options.optimize_filters_for_hits)
#ifndef ROCKSDB_LITE
, listeners(options.listeners) {
#else // ROCKSDB_LITE
{
#endif // ROCKSDB_LITE
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);
}
}
DBOptions::DBOptions()
: create_if_missing(false),
create_missing_column_families(false),
error_if_exists(false),
paranoid_checks(true),
env(Env::Default()),
rate_limiter(nullptr),
info_log(nullptr),
#ifdef NDEBUG
info_log_level(INFO_LEVEL),
#else
info_log_level(DEBUG_LEVEL),
#endif // NDEBUG
max_open_files(5000),
max_total_wal_size(0),
statistics(nullptr),
disableDataSync(false),
use_fsync(false),
db_log_dir(""),
wal_dir(""),
delete_obsolete_files_period_micros(6 * 60 * 60 * 1000000UL),
max_background_compactions(1),
max_background_flushes(1),
max_log_file_size(0),
log_file_time_to_roll(0),
keep_log_file_num(1000),
max_manifest_file_size(std::numeric_limits<uint64_t>::max()),
table_cache_numshardbits(4),
table_cache_remove_scan_count_limit(16),
WAL_ttl_seconds(0),
WAL_size_limit_MB(0),
manifest_preallocation_size(4 * 1024 * 1024),
allow_os_buffer(true),
allow_mmap_reads(false),
allow_mmap_writes(false),
is_fd_close_on_exec(true),
skip_log_error_on_recovery(false),
stats_dump_period_sec(3600),
advise_random_on_open(true),
db_write_buffer_size(0),
access_hint_on_compaction_start(NORMAL),
use_adaptive_mutex(false),
bytes_per_sync(0),
enable_thread_tracking(false) {
}
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),
info_log(options.info_log),
info_log_level(options.info_log_level),
max_open_files(options.max_open_files),
max_total_wal_size(options.max_total_wal_size),
statistics(options.statistics),
disableDataSync(options.disableDataSync),
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),
max_background_compactions(options.max_background_compactions),
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),
max_manifest_file_size(options.max_manifest_file_size),
table_cache_numshardbits(options.table_cache_numshardbits),
table_cache_remove_scan_count_limit(
options.table_cache_remove_scan_count_limit),
WAL_ttl_seconds(options.WAL_ttl_seconds),
WAL_size_limit_MB(options.WAL_size_limit_MB),
manifest_preallocation_size(options.manifest_preallocation_size),
allow_os_buffer(options.allow_os_buffer),
allow_mmap_reads(options.allow_mmap_reads),
allow_mmap_writes(options.allow_mmap_writes),
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),
access_hint_on_compaction_start(options.access_hint_on_compaction_start),
use_adaptive_mutex(options.use_adaptive_mutex),
bytes_per_sync(options.bytes_per_sync),
enable_thread_tracking(options.enable_thread_tracking) {}
static const char* const access_hints[] = {
"NONE", "NORMAL", "SEQUENTIAL", "WILLNEED"
};
void DBOptions::Dump(Logger* log) const {
Log(log," Options.error_if_exists: %d", error_if_exists);
Log(log," Options.create_if_missing: %d", create_if_missing);
Log(log," Options.paranoid_checks: %d", paranoid_checks);
Log(log," Options.env: %p", env);
Log(log," Options.info_log: %p", info_log.get());
Log(log," Options.max_open_files: %d", max_open_files);
Log(log," Options.max_total_wal_size: %" PRIu64, max_total_wal_size);
Log(log, " Options.disableDataSync: %d", disableDataSync);
Log(log, " Options.use_fsync: %d", use_fsync);
Log(log, " Options.max_log_file_size: %zu", max_log_file_size);
Log(log, "Options.max_manifest_file_size: %" PRIu64,
max_manifest_file_size);
Log(log, " Options.log_file_time_to_roll: %zu", log_file_time_to_roll);
Log(log, " Options.keep_log_file_num: %zu", keep_log_file_num);
Log(log, " Options.allow_os_buffer: %d", allow_os_buffer);
Log(log, " Options.allow_mmap_reads: %d", allow_mmap_reads);
Log(log, " Options.allow_mmap_writes: %d", allow_mmap_writes);
Log(log, " Options.create_missing_column_families: %d",
create_missing_column_families);
Log(log, " Options.db_log_dir: %s",
db_log_dir.c_str());
Log(log, " Options.wal_dir: %s",
wal_dir.c_str());
Log(log, " Options.table_cache_numshardbits: %d",
table_cache_numshardbits);
Log(log, " Options.table_cache_remove_scan_count_limit: %d",
table_cache_remove_scan_count_limit);
Log(log, " Options.delete_obsolete_files_period_micros: %" PRIu64,
delete_obsolete_files_period_micros);
Log(log, " Options.max_background_compactions: %d",
max_background_compactions);
Log(log, " Options.max_background_flushes: %d",
max_background_flushes);
Log(log, " Options.WAL_ttl_seconds: %" PRIu64,
WAL_ttl_seconds);
Log(log, " Options.WAL_size_limit_MB: %" PRIu64,
WAL_size_limit_MB);
Log(log, " Options.manifest_preallocation_size: %zu",
manifest_preallocation_size);
Log(log, " Options.allow_os_buffer: %d",
allow_os_buffer);
Log(log, " Options.allow_mmap_reads: %d",
allow_mmap_reads);
Log(log, " Options.allow_mmap_writes: %d",
allow_mmap_writes);
Log(log, " Options.is_fd_close_on_exec: %d",
is_fd_close_on_exec);
Log(log, " Options.stats_dump_period_sec: %u",
stats_dump_period_sec);
Log(log, " Options.advise_random_on_open: %d",
advise_random_on_open);
Log(log, " Options.db_write_buffer_size: %zd",
db_write_buffer_size);
Log(log, " Options.access_hint_on_compaction_start: %s",
access_hints[access_hint_on_compaction_start]);
Log(log, " Options.use_adaptive_mutex: %d",
use_adaptive_mutex);
Log(log, " Options.rate_limiter: %p",
rate_limiter.get());
Log(log, " Options.bytes_per_sync: %" PRIu64,
bytes_per_sync);
Log(log, " Options.enable_thread_tracking: %d",
enable_thread_tracking);
} // DBOptions::Dump
void ColumnFamilyOptions::Dump(Logger* log) const {
Log(log, " Options.comparator: %s", comparator->Name());
Log(log, " Options.merge_operator: %s",
merge_operator ? merge_operator->Name() : "None");
Log(log, " Options.compaction_filter: %s",
compaction_filter ? compaction_filter->Name() : "None");
Log(log, " Options.compaction_filter_factory: %s",
compaction_filter_factory->Name());
Log(log, " Options.compaction_filter_factory_v2: %s",
compaction_filter_factory_v2->Name());
Log(log, " Options.memtable_factory: %s", memtable_factory->Name());
Log(log, " Options.table_factory: %s", table_factory->Name());
Log(log, " table_factory options: %s",
table_factory->GetPrintableTableOptions().c_str());
Log(log, " Options.write_buffer_size: %zd", write_buffer_size);
Log(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++) {
Log(log," Options.compression[%d]: %d",
i, compression_per_level[i]);
}
} else {
Log(log," Options.compression: %d", compression);
}
Log(log," Options.prefix_extractor: %s",
prefix_extractor == nullptr ? "nullptr" : prefix_extractor->Name());
Log(log," Options.num_levels: %d", num_levels);
Log(log," Options.min_write_buffer_number_to_merge: %d",
min_write_buffer_number_to_merge);
Log(log," Options.purge_redundant_kvs_while_flush: %d",
purge_redundant_kvs_while_flush);
Log(log," Options.compression_opts.window_bits: %d",
compression_opts.window_bits);
Log(log," Options.compression_opts.level: %d",
compression_opts.level);
Log(log," Options.compression_opts.strategy: %d",
compression_opts.strategy);
Log(log," Options.level0_file_num_compaction_trigger: %d",
level0_file_num_compaction_trigger);
Log(log," Options.level0_slowdown_writes_trigger: %d",
level0_slowdown_writes_trigger);
Log(log," Options.level0_stop_writes_trigger: %d",
level0_stop_writes_trigger);
Log(log," Options.max_mem_compaction_level: %d",
max_mem_compaction_level);
Log(log," Options.target_file_size_base: %" PRIu64,
target_file_size_base);
Log(log," Options.target_file_size_multiplier: %d",
target_file_size_multiplier);
Log(log," Options.max_bytes_for_level_base: %" PRIu64,
max_bytes_for_level_base);
Log(log," Options.max_bytes_for_level_multiplier: %d",
max_bytes_for_level_multiplier);
for (int i = 0; i < num_levels; i++) {
Log(log,"Options.max_bytes_for_level_multiplier_addtl[%d]: %d",
i, max_bytes_for_level_multiplier_additional[i]);
}
Log(log," Options.max_sequential_skip_in_iterations: %" PRIu64,
max_sequential_skip_in_iterations);
Log(log," Options.expanded_compaction_factor: %d",
expanded_compaction_factor);
Log(log," Options.source_compaction_factor: %d",
source_compaction_factor);
Log(log," Options.max_grandparent_overlap_factor: %d",
max_grandparent_overlap_factor);
Log(log," Options.arena_block_size: %zu",
arena_block_size);
Log(log," Options.soft_rate_limit: %.2f",
soft_rate_limit);
Log(log," Options.hard_rate_limit: %.2f",
hard_rate_limit);
Log(log," Options.rate_limit_delay_max_milliseconds: %u",
rate_limit_delay_max_milliseconds);
Log(log," Options.disable_auto_compactions: %d",
disable_auto_compactions);
Log(log," Options.purge_redundant_kvs_while_flush: %d",
purge_redundant_kvs_while_flush);
Log(log," Options.filter_deletes: %d",
filter_deletes);
Log(log, " Options.verify_checksums_in_compaction: %d",
verify_checksums_in_compaction);
Log(log," Options.compaction_style: %d",
compaction_style);
Log(log," Options.compaction_options_universal.size_ratio: %u",
compaction_options_universal.size_ratio);
Log(log,"Options.compaction_options_universal.min_merge_width: %u",
compaction_options_universal.min_merge_width);
Log(log,"Options.compaction_options_universal.max_merge_width: %u",
compaction_options_universal.max_merge_width);
Log(log,"Options.compaction_options_universal."
"max_size_amplification_percent: %u",
compaction_options_universal.max_size_amplification_percent);
Log(log,
"Options.compaction_options_universal.compression_size_percent: %d",
compaction_options_universal.compression_size_percent);
Log(log, "Options.compaction_options_fifo.max_table_files_size: %" PRIu64,
compaction_options_fifo.max_table_files_size);
std::string collector_names;
for (const auto& collector_factory : table_properties_collector_factories) {
collector_names.append(collector_factory->Name());
collector_names.append("; ");
}
Log(log, " Options.table_properties_collectors: %s",
collector_names.c_str());
Log(log, " Options.inplace_update_support: %d",
inplace_update_support);
Log(log, " Options.inplace_update_num_locks: %zd",
inplace_update_num_locks);
Log(log, " Options.min_partial_merge_operands: %u",
min_partial_merge_operands);
// TODO: easier config for bloom (maybe based on avg key/value size)
Log(log, " Options.memtable_prefix_bloom_bits: %d",
memtable_prefix_bloom_bits);
Log(log, " Options.memtable_prefix_bloom_probes: %d",
memtable_prefix_bloom_probes);
Log(log, " Options.memtable_prefix_bloom_huge_page_tlb_size: %zu",
memtable_prefix_bloom_huge_page_tlb_size);
Log(log, " Options.bloom_locality: %d",
bloom_locality);
Log(log, " Options.max_successive_merges: %zd",
max_successive_merges);
Log(log, " Options.optimize_fllters_for_hits: %d",
optimize_filters_for_hits);
} // ColumnFamilyOptions::Dump
void Options::Dump(Logger* log) const {
DBOptions::Dump(log);
ColumnFamilyOptions::Dump(log);
} // Options::Dump
//
// 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);
// no auto compactions please. The application should issue a
// manual compaction after all data is loaded into L0.
disable_auto_compactions = true;
disableDataSync = true;
// A manual compaction run should pick all files in L0 in
// a single compaction run.
source_compaction_factor = (1<<30);
// 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;
// The compaction would create large files in L1.
target_file_size_base = 256 * 1024 * 1024;
return this;
}
#ifndef ROCKSDB_LITE
// Optimization functions
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_factory.reset(NewHashLinkListRepFactory());
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;
}
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) {
XFUNC_TEST("", "managed_options", managed_options, xf_manage_options,
reinterpret_cast<ReadOptions*>(this));
}
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) {
XFUNC_TEST("", "managed_options", managed_options, xf_manage_options,
reinterpret_cast<ReadOptions*>(this));
}
#endif // ROCKSDB_LITE
} // namespace rocksdb