rocksdb/monitoring/statistics.cc
Andrew Kryczka ac39d6bec5 Core-local statistics
Summary:
This diff changes `StatisticsImpl` from a thread-local approach to a core-local one. The goal is to perform faster aggregations, particularly for applications that have many threads. There should be no behavior change.
Closes https://github.com/facebook/rocksdb/pull/2258

Differential Revision: D5016258

Pulled By: ajkr

fbshipit-source-id: 7d4d165b4a91d8110f0409d113d1be91f22d31a9
2017-05-23 10:42:59 -07:00

194 lines
6.2 KiB
C++

// Copyright (c) 2011-present, 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.
// This source code is also licensed under the GPLv2 license found in the
// COPYING file in the root directory of this source tree.
//
#include "monitoring/statistics.h"
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
#include "rocksdb/statistics.h"
#include "port/likely.h"
#include <algorithm>
#include <cstdio>
namespace rocksdb {
std::shared_ptr<Statistics> CreateDBStatistics() {
return std::make_shared<StatisticsImpl>(nullptr, false);
}
StatisticsImpl::StatisticsImpl(std::shared_ptr<Statistics> stats,
bool enable_internal_stats)
: stats_(std::move(stats)), enable_internal_stats_(enable_internal_stats) {}
StatisticsImpl::~StatisticsImpl() {}
uint64_t StatisticsImpl::getTickerCount(uint32_t tickerType) const {
MutexLock lock(&aggregate_lock_);
return getTickerCountLocked(tickerType);
}
uint64_t StatisticsImpl::getTickerCountLocked(uint32_t tickerType) const {
assert(
enable_internal_stats_ ?
tickerType < INTERNAL_TICKER_ENUM_MAX :
tickerType < TICKER_ENUM_MAX);
uint64_t res = 0;
for (size_t core_idx = 0; core_idx < per_core_stats_.Size(); ++core_idx) {
res += per_core_stats_.AccessAtCore(core_idx)->tickers_[tickerType];
}
return res;
}
void StatisticsImpl::histogramData(uint32_t histogramType,
HistogramData* const data) const {
MutexLock lock(&aggregate_lock_);
getHistogramImplLocked(histogramType)->Data(data);
}
std::unique_ptr<HistogramImpl> StatisticsImpl::getHistogramImplLocked(
uint32_t histogramType) const {
assert(
enable_internal_stats_ ?
histogramType < INTERNAL_HISTOGRAM_ENUM_MAX :
histogramType < HISTOGRAM_ENUM_MAX);
std::unique_ptr<HistogramImpl> res_hist(new HistogramImpl());
for (size_t core_idx = 0; core_idx < per_core_stats_.Size(); ++core_idx) {
res_hist->Merge(
per_core_stats_.AccessAtCore(core_idx)->histograms_[histogramType]);
}
return res_hist;
}
std::string StatisticsImpl::getHistogramString(uint32_t histogramType) const {
MutexLock lock(&aggregate_lock_);
return getHistogramImplLocked(histogramType)->ToString();
}
void StatisticsImpl::setTickerCount(uint32_t tickerType, uint64_t count) {
{
MutexLock lock(&aggregate_lock_);
setTickerCountLocked(tickerType, count);
}
if (stats_ && tickerType < TICKER_ENUM_MAX) {
stats_->setTickerCount(tickerType, count);
}
}
void StatisticsImpl::setTickerCountLocked(uint32_t tickerType, uint64_t count) {
assert(enable_internal_stats_ ? tickerType < INTERNAL_TICKER_ENUM_MAX
: tickerType < TICKER_ENUM_MAX);
for (size_t core_idx = 0; core_idx < per_core_stats_.Size(); ++core_idx) {
if (core_idx == 0) {
per_core_stats_.AccessAtCore(core_idx)->tickers_[tickerType] = count;
} else {
per_core_stats_.AccessAtCore(core_idx)->tickers_[tickerType] = 0;
}
}
}
uint64_t StatisticsImpl::getAndResetTickerCount(uint32_t tickerType) {
uint64_t sum = 0;
{
MutexLock lock(&aggregate_lock_);
assert(enable_internal_stats_ ? tickerType < INTERNAL_TICKER_ENUM_MAX
: tickerType < TICKER_ENUM_MAX);
for (size_t core_idx = 0; core_idx < per_core_stats_.Size(); ++core_idx) {
sum +=
per_core_stats_.AccessAtCore(core_idx)->tickers_[tickerType].exchange(
0, std::memory_order_relaxed);
}
}
if (stats_ && tickerType < TICKER_ENUM_MAX) {
stats_->setTickerCount(tickerType, 0);
}
return sum;
}
void StatisticsImpl::recordTick(uint32_t tickerType, uint64_t count) {
assert(
enable_internal_stats_ ?
tickerType < INTERNAL_TICKER_ENUM_MAX :
tickerType < TICKER_ENUM_MAX);
per_core_stats_.Access()->tickers_[tickerType].fetch_add(
count, std::memory_order_relaxed);
if (stats_ && tickerType < TICKER_ENUM_MAX) {
stats_->recordTick(tickerType, count);
}
}
void StatisticsImpl::measureTime(uint32_t histogramType, uint64_t value) {
assert(
enable_internal_stats_ ?
histogramType < INTERNAL_HISTOGRAM_ENUM_MAX :
histogramType < HISTOGRAM_ENUM_MAX);
per_core_stats_.Access()->histograms_[histogramType].Add(value);
if (stats_ && histogramType < HISTOGRAM_ENUM_MAX) {
stats_->measureTime(histogramType, value);
}
}
Status StatisticsImpl::Reset() {
MutexLock lock(&aggregate_lock_);
for (uint32_t i = 0; i < TICKER_ENUM_MAX; ++i) {
setTickerCountLocked(i, 0);
}
for (uint32_t i = 0; i < HISTOGRAM_ENUM_MAX; ++i) {
for (size_t core_idx = 0; core_idx < per_core_stats_.Size(); ++core_idx) {
per_core_stats_.AccessAtCore(core_idx)->histograms_[i].Clear();
}
}
return Status::OK();
}
namespace {
// a buffer size used for temp string buffers
const int kTmpStrBufferSize = 200;
} // namespace
std::string StatisticsImpl::ToString() const {
MutexLock lock(&aggregate_lock_);
std::string res;
res.reserve(20000);
for (const auto& t : TickersNameMap) {
if (t.first < TICKER_ENUM_MAX || enable_internal_stats_) {
char buffer[kTmpStrBufferSize];
snprintf(buffer, kTmpStrBufferSize, "%s COUNT : %" PRIu64 "\n",
t.second.c_str(), getTickerCountLocked(t.first));
res.append(buffer);
}
}
for (const auto& h : HistogramsNameMap) {
if (h.first < HISTOGRAM_ENUM_MAX || enable_internal_stats_) {
char buffer[kTmpStrBufferSize];
HistogramData hData;
getHistogramImplLocked(h.first)->Data(&hData);
snprintf(
buffer, kTmpStrBufferSize,
"%s statistics Percentiles :=> 50 : %f 95 : %f 99 : %f 100 : %f\n",
h.second.c_str(), hData.median, hData.percentile95,
hData.percentile99, hData.max);
res.append(buffer);
}
}
res.shrink_to_fit();
return res;
}
bool StatisticsImpl::HistEnabledForType(uint32_t type) const {
if (LIKELY(!enable_internal_stats_)) {
return type < HISTOGRAM_ENUM_MAX;
}
return true;
}
} // namespace rocksdb