rocksdb/options/cf_options.h
Zhongyi Xie 2f41ecfe75 Refactor trimming logic for immutable memtables (#5022)
Summary:
MyRocks currently sets `max_write_buffer_number_to_maintain` in order to maintain enough history for transaction conflict checking. The effectiveness of this approach depends on the size of memtables. When memtables are small, it may not keep enough history; when memtables are large, this may consume too much memory.
We are proposing a new way to configure memtable list history: by limiting the memory usage of immutable memtables. The new option is `max_write_buffer_size_to_maintain` and it will take precedence over the old `max_write_buffer_number_to_maintain` if they are both set to non-zero values. The new option accounts for the total memory usage of flushed immutable memtables and mutable memtable. When the total usage exceeds the limit, RocksDB may start dropping immutable memtables (which is also called trimming history), starting from the oldest one.
The semantics of the old option actually works both as an upper bound and lower bound. History trimming will start if number of immutable memtables exceeds the limit, but it will never go below (limit-1) due to history trimming.
In order the mimic the behavior with the new option, history trimming will stop if dropping the next immutable memtable causes the total memory usage go below the size limit. For example, assuming the size limit is set to 64MB, and there are 3 immutable memtables with sizes of 20, 30, 30. Although the total memory usage is 80MB > 64MB, dropping the oldest memtable will reduce the memory usage to 60MB < 64MB, so in this case no memtable will be dropped.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5022

Differential Revision: D14394062

Pulled By: miasantreble

fbshipit-source-id: 60457a509c6af89d0993f988c9b5c2aa9e45f5c5
2019-08-23 13:55:34 -07:00

270 lines
8.9 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).
#pragma once
#include <string>
#include <vector>
#include "db/dbformat.h"
#include "options/db_options.h"
#include "rocksdb/options.h"
#include "util/compression.h"
namespace rocksdb {
// ImmutableCFOptions is a data struct used by RocksDB internal. It contains a
// subset of Options that should not be changed during the entire lifetime
// of DB. Raw pointers defined in this struct do not have ownership to the data
// they point to. Options contains std::shared_ptr to these data.
struct ImmutableCFOptions {
ImmutableCFOptions();
explicit ImmutableCFOptions(const Options& options);
ImmutableCFOptions(const ImmutableDBOptions& db_options,
const ColumnFamilyOptions& cf_options);
CompactionStyle compaction_style;
CompactionPri compaction_pri;
const Comparator* user_comparator;
InternalKeyComparator internal_comparator;
MergeOperator* merge_operator;
const CompactionFilter* compaction_filter;
CompactionFilterFactory* compaction_filter_factory;
int min_write_buffer_number_to_merge;
int max_write_buffer_number_to_maintain;
int64_t max_write_buffer_size_to_maintain;
bool inplace_update_support;
UpdateStatus (*inplace_callback)(char* existing_value,
uint32_t* existing_value_size,
Slice delta_value,
std::string* merged_value);
Logger* info_log;
Statistics* statistics;
RateLimiter* rate_limiter;
InfoLogLevel info_log_level;
Env* env;
// Allow the OS to mmap file for reading sst tables. Default: false
bool allow_mmap_reads;
// Allow the OS to mmap file for writing. Default: false
bool allow_mmap_writes;
std::vector<DbPath> db_paths;
MemTableRepFactory* memtable_factory;
TableFactory* table_factory;
Options::TablePropertiesCollectorFactories
table_properties_collector_factories;
bool advise_random_on_open;
// This options is required by PlainTableReader. May need to move it
// to PlainTableOptions just like bloom_bits_per_key
uint32_t bloom_locality;
bool purge_redundant_kvs_while_flush;
bool use_fsync;
std::vector<CompressionType> compression_per_level;
CompressionType bottommost_compression;
CompressionOptions bottommost_compression_opts;
CompressionOptions compression_opts;
bool level_compaction_dynamic_level_bytes;
Options::AccessHint access_hint_on_compaction_start;
bool new_table_reader_for_compaction_inputs;
int num_levels;
bool optimize_filters_for_hits;
bool force_consistency_checks;
bool allow_ingest_behind;
bool preserve_deletes;
// A vector of EventListeners which callback functions will be called
// when specific RocksDB event happens.
std::vector<std::shared_ptr<EventListener>> listeners;
std::shared_ptr<Cache> row_cache;
uint32_t max_subcompactions;
const SliceTransform* memtable_insert_with_hint_prefix_extractor;
std::vector<DbPath> cf_paths;
std::shared_ptr<ConcurrentTaskLimiter> compaction_thread_limiter;
};
struct MutableCFOptions {
explicit MutableCFOptions(const ColumnFamilyOptions& options)
: write_buffer_size(options.write_buffer_size),
max_write_buffer_number(options.max_write_buffer_number),
arena_block_size(options.arena_block_size),
memtable_prefix_bloom_size_ratio(
options.memtable_prefix_bloom_size_ratio),
memtable_whole_key_filtering(options.memtable_whole_key_filtering),
memtable_huge_page_size(options.memtable_huge_page_size),
max_successive_merges(options.max_successive_merges),
inplace_update_num_locks(options.inplace_update_num_locks),
prefix_extractor(options.prefix_extractor),
disable_auto_compactions(options.disable_auto_compactions),
soft_pending_compaction_bytes_limit(
options.soft_pending_compaction_bytes_limit),
hard_pending_compaction_bytes_limit(
options.hard_pending_compaction_bytes_limit),
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_compaction_bytes(options.max_compaction_bytes),
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),
snap_refresh_nanos(options.snap_refresh_nanos),
max_bytes_for_level_multiplier(options.max_bytes_for_level_multiplier),
ttl(options.ttl),
periodic_compaction_seconds(options.periodic_compaction_seconds),
max_bytes_for_level_multiplier_additional(
options.max_bytes_for_level_multiplier_additional),
compaction_options_fifo(options.compaction_options_fifo),
compaction_options_universal(options.compaction_options_universal),
max_sequential_skip_in_iterations(
options.max_sequential_skip_in_iterations),
paranoid_file_checks(options.paranoid_file_checks),
report_bg_io_stats(options.report_bg_io_stats),
compression(options.compression),
sample_for_compression(options.sample_for_compression) {
RefreshDerivedOptions(options.num_levels, options.compaction_style);
}
MutableCFOptions()
: write_buffer_size(0),
max_write_buffer_number(0),
arena_block_size(0),
memtable_prefix_bloom_size_ratio(0),
memtable_whole_key_filtering(false),
memtable_huge_page_size(0),
max_successive_merges(0),
inplace_update_num_locks(0),
prefix_extractor(nullptr),
disable_auto_compactions(false),
soft_pending_compaction_bytes_limit(0),
hard_pending_compaction_bytes_limit(0),
level0_file_num_compaction_trigger(0),
level0_slowdown_writes_trigger(0),
level0_stop_writes_trigger(0),
max_compaction_bytes(0),
target_file_size_base(0),
target_file_size_multiplier(0),
max_bytes_for_level_base(0),
snap_refresh_nanos(0),
max_bytes_for_level_multiplier(0),
ttl(0),
periodic_compaction_seconds(0),
compaction_options_fifo(),
max_sequential_skip_in_iterations(0),
paranoid_file_checks(false),
report_bg_io_stats(false),
compression(Snappy_Supported() ? kSnappyCompression : kNoCompression),
sample_for_compression(0) {}
explicit MutableCFOptions(const Options& options);
// Must be called after any change to MutableCFOptions
void RefreshDerivedOptions(int num_levels, CompactionStyle compaction_style);
void RefreshDerivedOptions(const ImmutableCFOptions& ioptions) {
RefreshDerivedOptions(ioptions.num_levels, ioptions.compaction_style);
}
int MaxBytesMultiplerAdditional(int level) const {
if (level >=
static_cast<int>(max_bytes_for_level_multiplier_additional.size())) {
return 1;
}
return max_bytes_for_level_multiplier_additional[level];
}
void Dump(Logger* log) const;
// Memtable related options
size_t write_buffer_size;
int max_write_buffer_number;
size_t arena_block_size;
double memtable_prefix_bloom_size_ratio;
bool memtable_whole_key_filtering;
size_t memtable_huge_page_size;
size_t max_successive_merges;
size_t inplace_update_num_locks;
std::shared_ptr<const SliceTransform> prefix_extractor;
// Compaction related options
bool disable_auto_compactions;
uint64_t soft_pending_compaction_bytes_limit;
uint64_t hard_pending_compaction_bytes_limit;
int level0_file_num_compaction_trigger;
int level0_slowdown_writes_trigger;
int level0_stop_writes_trigger;
uint64_t max_compaction_bytes;
uint64_t target_file_size_base;
int target_file_size_multiplier;
uint64_t max_bytes_for_level_base;
uint64_t snap_refresh_nanos;
double max_bytes_for_level_multiplier;
uint64_t ttl;
uint64_t periodic_compaction_seconds;
std::vector<int> max_bytes_for_level_multiplier_additional;
CompactionOptionsFIFO compaction_options_fifo;
CompactionOptionsUniversal compaction_options_universal;
// Misc options
uint64_t max_sequential_skip_in_iterations;
bool paranoid_file_checks;
bool report_bg_io_stats;
CompressionType compression;
uint64_t sample_for_compression;
// Derived options
// Per-level target file size.
std::vector<uint64_t> max_file_size;
};
uint64_t MultiplyCheckOverflow(uint64_t op1, double op2);
// Get the max file size in a given level.
uint64_t MaxFileSizeForLevel(const MutableCFOptions& cf_options,
int level, CompactionStyle compaction_style, int base_level = 1,
bool level_compaction_dynamic_level_bytes = false);
} // namespace rocksdb