fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
291 lines
10 KiB
291 lines
10 KiB
// 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.
|
|
//
|
|
// 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.
|
|
|
|
#ifndef __STDC_FORMAT_MACROS
|
|
#define __STDC_FORMAT_MACROS
|
|
#endif
|
|
|
|
#include "util/histogram.h"
|
|
|
|
#include <inttypes.h>
|
|
#include <cassert>
|
|
#include <math.h>
|
|
#include <stdio.h>
|
|
|
|
#include "port/port.h"
|
|
|
|
namespace rocksdb {
|
|
|
|
HistogramBucketMapper::HistogramBucketMapper()
|
|
:
|
|
// Add newer bucket index here.
|
|
// Should be always added in sorted order.
|
|
// If you change this, you also need to change
|
|
// size of array buckets_ in HistogramImpl
|
|
bucketValues_(
|
|
{1, 2, 3, 4, 5, 6,
|
|
7, 8, 9, 10, 12, 14,
|
|
16, 18, 20, 25, 30, 35,
|
|
40, 45, 50, 60, 70, 80,
|
|
90, 100, 120, 140, 160, 180,
|
|
200, 250, 300, 350, 400, 450,
|
|
500, 600, 700, 800, 900, 1000,
|
|
1200, 1400, 1600, 1800, 2000, 2500,
|
|
3000, 3500, 4000, 4500, 5000, 6000,
|
|
7000, 8000, 9000, 10000, 12000, 14000,
|
|
16000, 18000, 20000, 25000, 30000, 35000,
|
|
40000, 45000, 50000, 60000, 70000, 80000,
|
|
90000, 100000, 120000, 140000, 160000, 180000,
|
|
200000, 250000, 300000, 350000, 400000, 450000,
|
|
500000, 600000, 700000, 800000, 900000, 1000000,
|
|
1200000, 1400000, 1600000, 1800000, 2000000, 2500000,
|
|
3000000, 3500000, 4000000, 4500000, 5000000, 6000000,
|
|
7000000, 8000000, 9000000, 10000000, 12000000, 14000000,
|
|
16000000, 18000000, 20000000, 25000000, 30000000, 35000000,
|
|
40000000, 45000000, 50000000, 60000000, 70000000, 80000000,
|
|
90000000, 100000000, 120000000, 140000000, 160000000, 180000000,
|
|
200000000, 250000000, 300000000, 350000000, 400000000, 450000000,
|
|
500000000, 600000000, 700000000, 800000000, 900000000, 1000000000}),
|
|
maxBucketValue_(bucketValues_.back()),
|
|
minBucketValue_(bucketValues_.front()) {
|
|
for (size_t i =0; i < bucketValues_.size(); ++i) {
|
|
valueIndexMap_[bucketValues_[i]] = i;
|
|
}
|
|
}
|
|
|
|
size_t HistogramBucketMapper::IndexForValue(const uint64_t value) const {
|
|
if (value >= maxBucketValue_) {
|
|
return bucketValues_.size() - 1;
|
|
} else if ( value >= minBucketValue_ ) {
|
|
std::map<uint64_t, uint64_t>::const_iterator lowerBound =
|
|
valueIndexMap_.lower_bound(value);
|
|
if (lowerBound != valueIndexMap_.end()) {
|
|
return static_cast<size_t>(lowerBound->second);
|
|
} else {
|
|
return 0;
|
|
}
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
namespace {
|
|
const HistogramBucketMapper bucketMapper;
|
|
}
|
|
|
|
HistogramStat::HistogramStat()
|
|
: num_buckets_(bucketMapper.BucketCount()) {
|
|
assert(num_buckets_ == sizeof(buckets_) / sizeof(*buckets_));
|
|
Clear();
|
|
}
|
|
|
|
void HistogramStat::Clear() {
|
|
min_.store(bucketMapper.LastValue(), std::memory_order_relaxed);
|
|
max_.store(0, std::memory_order_relaxed);
|
|
num_.store(0, std::memory_order_relaxed);
|
|
sum_.store(0, std::memory_order_relaxed);
|
|
sum_squares_.store(0, std::memory_order_relaxed);
|
|
for (unsigned int b = 0; b < num_buckets_; b++) {
|
|
buckets_[b].store(0, std::memory_order_relaxed);
|
|
}
|
|
};
|
|
|
|
bool HistogramStat::Empty() const { return num() == 0; }
|
|
|
|
void HistogramStat::Add(uint64_t value) {
|
|
// This function is designed to be lock free, as it's in the critical path
|
|
// of any operation. Each individual value is atomic and the order of updates
|
|
// by concurrent threads is tolerable.
|
|
const size_t index = bucketMapper.IndexForValue(value);
|
|
assert(index < num_buckets_);
|
|
buckets_[index].fetch_add(1, std::memory_order_relaxed);
|
|
|
|
uint64_t old_min = min();
|
|
while (value < old_min && !min_.compare_exchange_weak(old_min, value)) {}
|
|
|
|
uint64_t old_max = max();
|
|
while (value > old_max && !max_.compare_exchange_weak(old_max, value)) {}
|
|
|
|
num_.fetch_add(1, std::memory_order_relaxed);
|
|
sum_.fetch_add(value, std::memory_order_relaxed);
|
|
sum_squares_.fetch_add(value * value, std::memory_order_relaxed);
|
|
}
|
|
|
|
void HistogramStat::Merge(const HistogramStat& other) {
|
|
// This function needs to be performned with the outer lock acquired
|
|
// However, atomic operation on every member is still need, since Add()
|
|
// requires no lock and value update can still happen concurrently
|
|
uint64_t old_min = min();
|
|
uint64_t other_min = other.min();
|
|
while (other_min < old_min &&
|
|
!min_.compare_exchange_weak(old_min, other_min)) {}
|
|
|
|
uint64_t old_max = max();
|
|
uint64_t other_max = other.max();
|
|
while (other_max > old_max &&
|
|
!max_.compare_exchange_weak(old_max, other_max)) {}
|
|
|
|
num_.fetch_add(other.num(), std::memory_order_relaxed);
|
|
sum_.fetch_add(other.sum(), std::memory_order_relaxed);
|
|
sum_squares_.fetch_add(other.sum_squares(), std::memory_order_relaxed);
|
|
for (unsigned int b = 0; b < num_buckets_; b++) {
|
|
buckets_[b].fetch_add(other.bucket_at(b), std::memory_order_relaxed);
|
|
}
|
|
}
|
|
|
|
double HistogramStat::Median() const {
|
|
return Percentile(50.0);
|
|
}
|
|
|
|
double HistogramStat::Percentile(double p) const {
|
|
double threshold = num() * (p / 100.0);
|
|
uint64_t cumulative_sum = 0;
|
|
for (unsigned int b = 0; b < num_buckets_; b++) {
|
|
uint64_t bucket_value = bucket_at(b);
|
|
cumulative_sum += bucket_value;
|
|
if (cumulative_sum >= threshold) {
|
|
// Scale linearly within this bucket
|
|
uint64_t left_point = (b == 0) ? 0 : bucketMapper.BucketLimit(b-1);
|
|
uint64_t right_point = bucketMapper.BucketLimit(b);
|
|
uint64_t left_sum = cumulative_sum - bucket_value;
|
|
uint64_t right_sum = cumulative_sum;
|
|
double pos = 0;
|
|
uint64_t right_left_diff = right_sum - left_sum;
|
|
if (right_left_diff != 0) {
|
|
pos = (threshold - left_sum) / right_left_diff;
|
|
}
|
|
double r = left_point + (right_point - left_point) * pos;
|
|
uint64_t cur_min = min();
|
|
uint64_t cur_max = max();
|
|
if (r < cur_min) r = static_cast<double>(cur_min);
|
|
if (r > cur_max) r = static_cast<double>(cur_max);
|
|
return r;
|
|
}
|
|
}
|
|
return static_cast<double>(max());
|
|
}
|
|
|
|
double HistogramStat::Average() const {
|
|
uint64_t cur_num = num();
|
|
uint64_t cur_sum = sum();
|
|
if (cur_num == 0) return 0;
|
|
return static_cast<double>(cur_sum) / static_cast<double>(cur_num);
|
|
}
|
|
|
|
double HistogramStat::StandardDeviation() const {
|
|
uint64_t cur_num = num();
|
|
uint64_t cur_sum = sum();
|
|
uint64_t cur_sum_squares = sum_squares();
|
|
if (cur_num == 0) return 0;
|
|
double variance =
|
|
static_cast<double>(cur_sum_squares * cur_num - cur_sum * cur_sum) /
|
|
static_cast<double>(cur_num * cur_num);
|
|
return sqrt(variance);
|
|
}
|
|
std::string HistogramStat::ToString() const {
|
|
uint64_t cur_num = num();
|
|
std::string r;
|
|
char buf[1650];
|
|
snprintf(buf, sizeof(buf),
|
|
"Count: %" PRIu64 " Average: %.4f StdDev: %.2f\n",
|
|
cur_num, Average(), StandardDeviation());
|
|
r.append(buf);
|
|
snprintf(buf, sizeof(buf),
|
|
"Min: %" PRIu64 " Median: %.4f Max: %" PRIu64 "\n",
|
|
(cur_num == 0 ? 0 : min()), Median(), (cur_num == 0 ? 0 : max()));
|
|
r.append(buf);
|
|
snprintf(buf, sizeof(buf),
|
|
"Percentiles: "
|
|
"P50: %.2f P75: %.2f P99: %.2f P99.9: %.2f P99.99: %.2f\n",
|
|
Percentile(50), Percentile(75), Percentile(99), Percentile(99.9),
|
|
Percentile(99.99));
|
|
r.append(buf);
|
|
r.append("------------------------------------------------------\n");
|
|
const double mult = 100.0 / cur_num;
|
|
uint64_t cumulative_sum = 0;
|
|
for (unsigned int b = 0; b < num_buckets_; b++) {
|
|
uint64_t bucket_value = bucket_at(b);
|
|
if (bucket_value <= 0.0) continue;
|
|
cumulative_sum += bucket_value;
|
|
snprintf(buf, sizeof(buf),
|
|
"[ %7" PRIu64 ", %7" PRIu64 " ) %8" PRIu64 " %7.3f%% %7.3f%% ",
|
|
(b == 0) ? 0 : bucketMapper.BucketLimit(b-1), // left
|
|
bucketMapper.BucketLimit(b), // right
|
|
bucket_value, // count
|
|
(mult * bucket_value), // percentage
|
|
(mult * cumulative_sum)); // cumulative percentage
|
|
r.append(buf);
|
|
|
|
// Add hash marks based on percentage; 20 marks for 100%.
|
|
size_t marks = static_cast<size_t>(mult * bucket_value / 5 + 0.5);
|
|
r.append(marks, '#');
|
|
r.push_back('\n');
|
|
}
|
|
return r;
|
|
}
|
|
|
|
void HistogramStat::Data(HistogramData * const data) const {
|
|
assert(data);
|
|
data->median = Median();
|
|
data->percentile95 = Percentile(95);
|
|
data->percentile99 = Percentile(99);
|
|
data->max = max();
|
|
data->average = Average();
|
|
data->standard_deviation = StandardDeviation();
|
|
}
|
|
|
|
void HistogramImpl::Clear() {
|
|
std::lock_guard<std::mutex> lock(mutex_);
|
|
stats_.Clear();
|
|
}
|
|
|
|
bool HistogramImpl::Empty() const {
|
|
return stats_.Empty();
|
|
}
|
|
|
|
void HistogramImpl::Add(uint64_t value) {
|
|
stats_.Add(value);
|
|
}
|
|
|
|
void HistogramImpl::Merge(const Histogram& other) {
|
|
if (strcmp(Name(), other.Name()) == 0) {
|
|
Merge(dynamic_cast<const HistogramImpl&>(other));
|
|
}
|
|
}
|
|
|
|
void HistogramImpl::Merge(const HistogramImpl& other) {
|
|
std::lock_guard<std::mutex> lock(mutex_);
|
|
stats_.Merge(other.stats_);
|
|
}
|
|
|
|
double HistogramImpl::Median() const {
|
|
return stats_.Median();
|
|
}
|
|
|
|
double HistogramImpl::Percentile(double p) const {
|
|
return stats_.Percentile(p);
|
|
}
|
|
|
|
double HistogramImpl::Average() const {
|
|
return stats_.Average();
|
|
}
|
|
|
|
double HistogramImpl::StandardDeviation() const {
|
|
return stats_.StandardDeviation();
|
|
}
|
|
|
|
std::string HistogramImpl::ToString() const {
|
|
return stats_.ToString();
|
|
}
|
|
|
|
void HistogramImpl::Data(HistogramData * const data) const {
|
|
stats_.Data(data);
|
|
}
|
|
|
|
} // namespace levedb
|
|
|