rocksdb/db/internal_stats.h
Igor Canadi 3c0dcf0e25 InternalStatistics
Summary:
In DBImpl we keep track of some statistics internally and expose them via GetProperty(). This diff encapsulates all the internal statistics into a class InternalStatisics. Most of it is copy/paste.

Apart from cleaning up db_impl.cc, this diff is also necessary for Column families, since every column family should have its own CompactionStats, MakeRoomForWrite-stall stats, etc. It's much easier to keep track of it in every column family if it's nicely encapsulated in its own class.

Test Plan: make check

Reviewers: dhruba, kailiu, haobo, sdong, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15273
2014-01-29 20:40:41 -08:00

150 lines
4.7 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.
//
#pragma once
#include "rocksdb/statistics.h"
#include "util/statistics.h"
#include "db/version_set.h"
#include <vector>
#include <string>
namespace rocksdb {
class InternalStats {
public:
enum WriteStallType {
LEVEL0_SLOWDOWN,
MEMTABLE_COMPACTION,
LEVEL0_NUM_FILES,
WRITE_STALLS_ENUM_MAX,
};
InternalStats(int num_levels, Env* env, Statistics* statistics)
: compaction_stats_(num_levels),
stall_micros_(WRITE_STALLS_ENUM_MAX, 0),
stall_counts_(WRITE_STALLS_ENUM_MAX, 0),
stall_leveln_slowdown_(num_levels, 0),
stall_leveln_slowdown_count_(num_levels, 0),
number_levels_(num_levels),
statistics_(statistics),
env_(env),
started_at_(env->NowMicros()) {}
// Per level compaction stats. compaction_stats_[level] stores the stats for
// compactions that produced data for the specified "level".
struct CompactionStats {
uint64_t micros;
// Bytes read from level N during compaction between levels N and N+1
int64_t bytes_readn;
// Bytes read from level N+1 during compaction between levels N and N+1
int64_t bytes_readnp1;
// Total bytes written during compaction between levels N and N+1
int64_t bytes_written;
// Files read from level N during compaction between levels N and N+1
int files_in_leveln;
// Files read from level N+1 during compaction between levels N and N+1
int files_in_levelnp1;
// Files written during compaction between levels N and N+1
int files_out_levelnp1;
// Number of compactions done
int count;
CompactionStats()
: micros(0),
bytes_readn(0),
bytes_readnp1(0),
bytes_written(0),
files_in_leveln(0),
files_in_levelnp1(0),
files_out_levelnp1(0),
count(0) {}
void Add(const CompactionStats& c) {
this->micros += c.micros;
this->bytes_readn += c.bytes_readn;
this->bytes_readnp1 += c.bytes_readnp1;
this->bytes_written += c.bytes_written;
this->files_in_leveln += c.files_in_leveln;
this->files_in_levelnp1 += c.files_in_levelnp1;
this->files_out_levelnp1 += c.files_out_levelnp1;
this->count += 1;
}
};
void AddCompactionStats(int level, const CompactionStats& stats) {
compaction_stats_[level].Add(stats);
}
void RecordWriteStall(WriteStallType write_stall_type, uint64_t micros) {
stall_micros_[write_stall_type] += micros;
stall_counts_[write_stall_type]++;
}
void RecordLevelNSlowdown(int level, uint64_t micros) {
stall_leveln_slowdown_[level] += micros;
stall_leveln_slowdown_count_[level] += micros;
}
bool GetProperty(const Slice& property, std::string* value,
VersionSet* version_set, int immsize);
private:
std::vector<CompactionStats> compaction_stats_;
// Used to compute per-interval statistics
struct StatsSnapshot {
uint64_t compaction_bytes_read_; // Bytes read by compaction
uint64_t compaction_bytes_written_; // Bytes written by compaction
uint64_t ingest_bytes_; // Bytes written by user
uint64_t wal_bytes_; // Bytes written to WAL
uint64_t wal_synced_; // Number of times WAL is synced
uint64_t write_with_wal_; // Number of writes that request WAL
// These count the number of writes processed by the calling thread or
// another thread.
uint64_t write_other_;
uint64_t write_self_;
double seconds_up_;
StatsSnapshot()
: compaction_bytes_read_(0),
compaction_bytes_written_(0),
ingest_bytes_(0),
wal_bytes_(0),
wal_synced_(0),
write_with_wal_(0),
write_other_(0),
write_self_(0),
seconds_up_(0) {}
};
// Counters from the previous time per-interval stats were computed
StatsSnapshot last_stats_;
// These count the number of microseconds for which MakeRoomForWrite stalls.
std::vector<uint64_t> stall_micros_;
std::vector<uint64_t> stall_counts_;
std::vector<uint64_t> stall_leveln_slowdown_;
std::vector<uint64_t> stall_leveln_slowdown_count_;
int number_levels_;
Statistics* statistics_;
Env* env_;
uint64_t started_at_;
};
} // namespace rocksdb