rocksdb/include/rocksdb/iostats_context.h
Peter Dillinger 1c8a012727 Add kCool Temperature (#14000)
Summary:
also requested by internal user, like kIce in https://github.com/facebook/rocksdb/issues/13927

Pull Request resolved: https://github.com/facebook/rocksdb/pull/14000

Test Plan: unit tests updated

Reviewed By: archang19

Differential Revision: D83200479

Pulled By: pdillinger

fbshipit-source-id: 31f2842d87bcad40227aeee9687ff5772393689c
2025-09-25 11:27:00 -07:00

120 lines
4 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 <stdint.h>
#include <string>
#include "rocksdb/perf_level.h"
/*
* NOTE:
* If you plan to add new metrics, please read documentation in perf_level.h and
* try to come up with a metric name that follows the naming conventions
* mentioned there. It helps to indicate the metric's starting enabling P
* erfLevel. Document this starting PerfLevel if the metric name cannot meet the
* naming conventions.
*/
// A thread local context for gathering io-stats efficiently and transparently.
// Use SetPerfLevel(PerfLevel::kEnableTime) to enable time stats.
//
namespace ROCKSDB_NAMESPACE {
// EXPERIMENTAL: the IO statistics for tiered storage. It matches with each
// item in Temperature class.
struct FileIOByTemperature {
// the number of bytes read to Temperature::kHot file
uint64_t hot_file_bytes_read;
// the number of bytes read to Temperature::kWarm file
uint64_t warm_file_bytes_read;
// the number of bytes read to Temperature::kCool file
uint64_t cool_file_bytes_read;
// the number of bytes read to Temperature::kCold file
uint64_t cold_file_bytes_read;
// the number of bytes read to Temperature::kIce file
uint64_t ice_file_bytes_read;
// total number of reads to Temperature::kHot file
uint64_t hot_file_read_count;
// total number of reads to Temperature::kWarm file
uint64_t warm_file_read_count;
// total number of reads to Temperature::kCool file
uint64_t cool_file_read_count;
// total number of reads to Temperature::kCold file
uint64_t cold_file_read_count;
// total number of reads to Temperature::kIce file
uint64_t ice_file_read_count;
// reset all the statistics to 0.
void Reset() {
hot_file_bytes_read = 0;
warm_file_bytes_read = 0;
cool_file_bytes_read = 0;
cold_file_bytes_read = 0;
ice_file_bytes_read = 0;
hot_file_read_count = 0;
warm_file_read_count = 0;
cool_file_read_count = 0;
cold_file_read_count = 0;
ice_file_read_count = 0;
}
};
struct IOStatsContext {
// reset all io-stats counter to zero
void Reset();
std::string ToString(bool exclude_zero_counters = false) const;
// the thread pool id
uint64_t thread_pool_id;
// number of bytes that has been written.
uint64_t bytes_written;
// number of bytes that has been read.
uint64_t bytes_read;
// time spent in open() and fopen().
uint64_t open_nanos;
// time spent in fallocate().
uint64_t allocate_nanos;
// time spent in write() and pwrite().
uint64_t write_nanos;
// time spent in read() and pread()
uint64_t read_nanos;
// time spent in sync_file_range().
uint64_t range_sync_nanos;
// time spent in fsync
uint64_t fsync_nanos;
// time spent in preparing write (fallocate etc).
uint64_t prepare_write_nanos;
// time spent in Logger::Logv().
uint64_t logger_nanos;
// CPU time spent in write() and pwrite()
uint64_t cpu_write_nanos;
// CPU time spent in read() and pread()
uint64_t cpu_read_nanos;
FileIOByTemperature file_io_stats_by_temperature;
// It is not consistent that whether iostats follows PerfLevel.Timer counters
// follows it but BackupEngine relies on counter metrics to always be there.
// Here we create a backdoor option to disable some counters, so that some
// existing stats are not polluted by file operations, such as logging, by
// turning this off.
bool disable_iostats = false;
};
// If RocksDB is compiled with -DNIOSTATS_CONTEXT, then a pointer to a global,
// non-thread-local IOStatsContext object will be returned. Attempts to update
// this object will be ignored, and reading from it will also be no-op.
// Otherwise, a pointer to a thread-local IOStatsContext object will be
// returned.
//
// This function never returns nullptr.
IOStatsContext* get_iostats_context();
} // namespace ROCKSDB_NAMESPACE