Implement a log-based histogram sampler to increase fidelity for small samples and maximum range for large samples.
This commit is contained in:
parent
46015b29ac
commit
3a538f4b00
@ -8,8 +8,10 @@
|
||||
|
||||
#ifdef USE_ADAPTIVE_SAMPLER
|
||||
#include "AdaptiveSampler.h"
|
||||
#else
|
||||
#elif defined(USE_HISTOGRAM_SAMPLER)
|
||||
#include "HistogramSampler.h"
|
||||
#else
|
||||
#include "LogHistogramSampler.h"
|
||||
#endif
|
||||
#include "AgentStats.h"
|
||||
#include "Operation.h"
|
||||
@ -21,8 +23,10 @@ class ConnectionStats {
|
||||
ConnectionStats(bool _sampling = true) :
|
||||
#ifdef USE_ADAPTIVE_SAMPLER
|
||||
get_sampler(100000), set_sampler(100000), op_sampler(100000),
|
||||
#else
|
||||
#elif defined(USE_HISTOGRAM_SAMPLER)
|
||||
get_sampler(10000,1), set_sampler(10000,1), op_sampler(1000,1),
|
||||
#else
|
||||
get_sampler(200), set_sampler(200), op_sampler(100),
|
||||
#endif
|
||||
rx_bytes(0), tx_bytes(0), gets(0), sets(0),
|
||||
get_misses(0), sampling(_sampling) {}
|
||||
@ -31,10 +35,14 @@ class ConnectionStats {
|
||||
AdaptiveSampler<Operation> get_sampler;
|
||||
AdaptiveSampler<Operation> set_sampler;
|
||||
AdaptiveSampler<double> op_sampler;
|
||||
#else
|
||||
#elif defined(USE_HISTOGRAM_SAMPLER)
|
||||
HistogramSampler get_sampler;
|
||||
HistogramSampler set_sampler;
|
||||
HistogramSampler op_sampler;
|
||||
#else
|
||||
LogHistogramSampler get_sampler;
|
||||
LogHistogramSampler set_sampler;
|
||||
LogHistogramSampler op_sampler;
|
||||
#endif
|
||||
|
||||
uint64_t rx_bytes, tx_bytes;
|
||||
@ -160,7 +168,7 @@ class ConnectionStats {
|
||||
);
|
||||
if (newline) printf("\n");
|
||||
}
|
||||
#else
|
||||
#elif defined(USE_HISTOGRAM_SAMPLER)
|
||||
void print_stats(const char *tag, HistogramSampler &sampler,
|
||||
bool newline = true) {
|
||||
if (sampler.total() == 0) {
|
||||
@ -170,6 +178,24 @@ class ConnectionStats {
|
||||
return;
|
||||
}
|
||||
|
||||
printf("%-7s %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f",
|
||||
tag, sampler.average(),
|
||||
sampler.get_nth(0), sampler.get_nth(1), sampler.get_nth(5),
|
||||
sampler.get_nth(10), sampler.get_nth(90),
|
||||
sampler.get_nth(95), sampler.get_nth(99));
|
||||
|
||||
if (newline) printf("\n");
|
||||
}
|
||||
#else
|
||||
void print_stats(const char *tag, LogHistogramSampler &sampler,
|
||||
bool newline = true) {
|
||||
if (sampler.total() == 0) {
|
||||
printf("%-7s %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f",
|
||||
tag, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0);
|
||||
if (newline) printf("\n");
|
||||
return;
|
||||
}
|
||||
|
||||
printf("%-7s %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f %7.1f",
|
||||
tag, sampler.average(),
|
||||
sampler.get_nth(0), sampler.get_nth(1), sampler.get_nth(5),
|
||||
|
93
LogHistogramSampler.h
Normal file
93
LogHistogramSampler.h
Normal file
@ -0,0 +1,93 @@
|
||||
/* -*- c++ -*- */
|
||||
#ifndef LOGHISTOGRAMSAMPLER_H
|
||||
#define LOGHISTOGRAMSAMPLER_H
|
||||
|
||||
#include <inttypes.h>
|
||||
|
||||
#include <assert.h>
|
||||
#include <vector>
|
||||
|
||||
#include "Operation.h"
|
||||
|
||||
#define _POW 1.1
|
||||
|
||||
class LogHistogramSampler {
|
||||
public:
|
||||
std::vector<uint64_t> bins;
|
||||
|
||||
double sum;
|
||||
|
||||
LogHistogramSampler() = delete;
|
||||
LogHistogramSampler(int _bins) : sum(0.0) {
|
||||
assert(_bins > 0);
|
||||
|
||||
bins.resize(_bins + 1, 0);
|
||||
}
|
||||
|
||||
void sample(const Operation &op) {
|
||||
sample(op.time());
|
||||
}
|
||||
|
||||
void sample(double s) {
|
||||
assert(s >= 0);
|
||||
size_t bin = log(s)/log(_POW);
|
||||
|
||||
sum += s;
|
||||
|
||||
// I("%f", sum);
|
||||
|
||||
if ((int64_t) bin < 0) {
|
||||
bin = 0;
|
||||
} else if (bin >= bins.size()) {
|
||||
bin = bins.size() - 1;
|
||||
}
|
||||
|
||||
bins[bin]++;
|
||||
}
|
||||
|
||||
double average() {
|
||||
// I("%f %d", sum, total());
|
||||
return sum / total();
|
||||
}
|
||||
|
||||
double minimum() {
|
||||
for (size_t i = 0; i < bins.size(); i++)
|
||||
if (bins[i] > 0) return pow(_POW, (double) i + 0.5);
|
||||
}
|
||||
|
||||
double get_nth(double nth) {
|
||||
uint64_t count = total();
|
||||
uint64_t n = 0;
|
||||
double target = count * nth/100;
|
||||
|
||||
for (size_t i = 0; i < bins.size(); i++) {
|
||||
n += bins[i];
|
||||
|
||||
if (n > target) { // The nth is inside bins[i].
|
||||
double left = target - (n - bins[i]);
|
||||
return pow(_POW, (double) i) +
|
||||
left / bins[i] * (pow(_POW, (double) (i+1)) - pow(_POW, (double) i));
|
||||
}
|
||||
}
|
||||
|
||||
return pow(_POW, bins.size());
|
||||
}
|
||||
|
||||
uint64_t total() {
|
||||
uint64_t sum = 0.0;
|
||||
|
||||
for (auto i: bins) sum += i;
|
||||
|
||||
return sum;
|
||||
}
|
||||
|
||||
void accumulate(const LogHistogramSampler &h) {
|
||||
assert(bins.size() == h.bins.size());
|
||||
|
||||
for (size_t i = 0; i < bins.size(); i++) bins[i] += h.bins[i];
|
||||
|
||||
sum += h.sum;
|
||||
}
|
||||
};
|
||||
|
||||
#endif // LOGHISTOGRAMSAMPLER_H
|
Loading…
Reference in New Issue
Block a user