9dc887ece0
Summary: Implement an experimental feature called "MemPurge", which consists in purging "garbage" bytes out of a memtable and reuse the memtable struct instead of making it immutable and eventually flushing its content to storage. The prototype is by default deactivated and is not intended for use. It is intended for correctness and validation testing. At the moment, the "MemPurge" feature can be switched on by using the `options.experimental_allow_mempurge` flag. For this early stage, when the allow_mempurge flag is set to `true`, all the flush operations will be rerouted to perform a MemPurge. This is a temporary design decision that will give us the time to explore meaningful heuristics to use MemPurge at the right time for relevant workloads . Moreover, the current MemPurge operation only supports `Puts`, `Deletes`, `DeleteRange` operations, and handles `Iterators` as well as `CompactionFilter`s that are invoked at flush time . Three unit tests are added to `db_flush_test.cc` to test if MemPurge works correctly (and checks that the previously mentioned operations are fully supported thoroughly tested). One noticeable design decision is the timing of the MemPurge operation in the memtable workflow: for this prototype, the mempurge happens when the memtable is switched (and usually made immutable). This is an inefficient process because it implies that the entirety of the MemPurge operation happens while holding the db_mutex. Future commits will make the MemPurge operation a background task (akin to the regular flush operation) and aim at drastically enhancing the performance of this operation. The MemPurge is also not fully "WAL-compatible" yet, but when the WAL is full, or when the regular MemPurge operation fails (or when the purged memtable still needs to be flushed), a regular flush operation takes place. Later commits will also correct these behaviors. Pull Request resolved: https://github.com/facebook/rocksdb/pull/8454 Reviewed By: anand1976 Differential Revision: D29433971 Pulled By: bjlemaire fbshipit-source-id: 6af48213554e35048a7e03816955100a80a26dc5
147 lines
4.6 KiB
C++
147 lines
4.6 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 "rocksdb/options.h"
|
|
|
|
namespace ROCKSDB_NAMESPACE {
|
|
class SystemClock;
|
|
|
|
struct ImmutableDBOptions {
|
|
static const char* kName() { return "ImmutableDBOptions"; }
|
|
ImmutableDBOptions();
|
|
explicit ImmutableDBOptions(const DBOptions& options);
|
|
|
|
void Dump(Logger* log) const;
|
|
|
|
bool create_if_missing;
|
|
bool create_missing_column_families;
|
|
bool error_if_exists;
|
|
bool paranoid_checks;
|
|
bool flush_verify_memtable_count;
|
|
bool track_and_verify_wals_in_manifest;
|
|
Env* env;
|
|
std::shared_ptr<RateLimiter> rate_limiter;
|
|
std::shared_ptr<SstFileManager> sst_file_manager;
|
|
std::shared_ptr<Logger> info_log;
|
|
InfoLogLevel info_log_level;
|
|
int max_file_opening_threads;
|
|
std::shared_ptr<Statistics> statistics;
|
|
bool use_fsync;
|
|
std::vector<DbPath> db_paths;
|
|
std::string db_log_dir;
|
|
std::string wal_dir;
|
|
size_t max_log_file_size;
|
|
size_t log_file_time_to_roll;
|
|
size_t keep_log_file_num;
|
|
size_t recycle_log_file_num;
|
|
uint64_t max_manifest_file_size;
|
|
int table_cache_numshardbits;
|
|
uint64_t WAL_ttl_seconds;
|
|
uint64_t WAL_size_limit_MB;
|
|
uint64_t max_write_batch_group_size_bytes;
|
|
size_t manifest_preallocation_size;
|
|
bool allow_mmap_reads;
|
|
bool allow_mmap_writes;
|
|
bool use_direct_reads;
|
|
bool use_direct_io_for_flush_and_compaction;
|
|
bool allow_fallocate;
|
|
bool is_fd_close_on_exec;
|
|
bool advise_random_on_open;
|
|
bool experimental_allow_mempurge;
|
|
size_t db_write_buffer_size;
|
|
std::shared_ptr<WriteBufferManager> write_buffer_manager;
|
|
DBOptions::AccessHint access_hint_on_compaction_start;
|
|
bool new_table_reader_for_compaction_inputs;
|
|
size_t random_access_max_buffer_size;
|
|
bool use_adaptive_mutex;
|
|
std::vector<std::shared_ptr<EventListener>> listeners;
|
|
bool enable_thread_tracking;
|
|
bool enable_pipelined_write;
|
|
bool unordered_write;
|
|
bool allow_concurrent_memtable_write;
|
|
bool enable_write_thread_adaptive_yield;
|
|
uint64_t write_thread_max_yield_usec;
|
|
uint64_t write_thread_slow_yield_usec;
|
|
bool skip_stats_update_on_db_open;
|
|
bool skip_checking_sst_file_sizes_on_db_open;
|
|
WALRecoveryMode wal_recovery_mode;
|
|
bool allow_2pc;
|
|
std::shared_ptr<Cache> row_cache;
|
|
#ifndef ROCKSDB_LITE
|
|
WalFilter* wal_filter;
|
|
#endif // ROCKSDB_LITE
|
|
bool fail_if_options_file_error;
|
|
bool dump_malloc_stats;
|
|
bool avoid_flush_during_recovery;
|
|
bool allow_ingest_behind;
|
|
bool preserve_deletes;
|
|
bool two_write_queues;
|
|
bool manual_wal_flush;
|
|
bool atomic_flush;
|
|
bool avoid_unnecessary_blocking_io;
|
|
bool persist_stats_to_disk;
|
|
bool write_dbid_to_manifest;
|
|
size_t log_readahead_size;
|
|
std::shared_ptr<FileChecksumGenFactory> file_checksum_gen_factory;
|
|
bool best_efforts_recovery;
|
|
int max_bgerror_resume_count;
|
|
uint64_t bgerror_resume_retry_interval;
|
|
bool allow_data_in_errors;
|
|
std::string db_host_id;
|
|
FileTypeSet checksum_handoff_file_types;
|
|
// Convenience/Helper objects that are not part of the base DBOptions
|
|
std::shared_ptr<FileSystem> fs;
|
|
SystemClock* clock;
|
|
Statistics* stats;
|
|
Logger* logger;
|
|
std::shared_ptr<CompactionService> compaction_service;
|
|
};
|
|
|
|
struct MutableDBOptions {
|
|
static const char* kName() { return "MutableDBOptions"; }
|
|
MutableDBOptions();
|
|
explicit MutableDBOptions(const MutableDBOptions& options) = default;
|
|
explicit MutableDBOptions(const DBOptions& options);
|
|
|
|
void Dump(Logger* log) const;
|
|
|
|
int max_background_jobs;
|
|
int base_background_compactions;
|
|
int max_background_compactions;
|
|
uint32_t max_subcompactions;
|
|
bool avoid_flush_during_shutdown;
|
|
size_t writable_file_max_buffer_size;
|
|
uint64_t delayed_write_rate;
|
|
uint64_t max_total_wal_size;
|
|
uint64_t delete_obsolete_files_period_micros;
|
|
unsigned int stats_dump_period_sec;
|
|
unsigned int stats_persist_period_sec;
|
|
size_t stats_history_buffer_size;
|
|
int max_open_files;
|
|
uint64_t bytes_per_sync;
|
|
uint64_t wal_bytes_per_sync;
|
|
bool strict_bytes_per_sync;
|
|
size_t compaction_readahead_size;
|
|
int max_background_flushes;
|
|
};
|
|
|
|
#ifndef ROCKSDB_LITE
|
|
Status GetStringFromMutableDBOptions(const ConfigOptions& config_options,
|
|
const MutableDBOptions& mutable_opts,
|
|
std::string* opt_string);
|
|
|
|
Status GetMutableDBOptionsFromStrings(
|
|
const MutableDBOptions& base_options,
|
|
const std::unordered_map<std::string, std::string>& options_map,
|
|
MutableDBOptions* new_options);
|
|
#endif // ROCKSDB_LITE
|
|
|
|
} // namespace ROCKSDB_NAMESPACE
|