gperftools/benchmark/run_benchmark.cc

121 lines
3.5 KiB
C++

// -*- Mode: C; c-basic-offset: 2; indent-tabs-mode: nil -*-
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "run_benchmark.h"
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
struct internal_bench {
bench_body body;
uintptr_t param;
};
static void run_body(struct internal_bench *b, long iterations)
{
b->body(iterations, b->param);
}
static double measure_once(struct internal_bench *b, long iterations)
{
struct timeval tv_before, tv_after;
int rv;
double time;
rv = gettimeofday(&tv_before, NULL);
if (rv) {
perror("gettimeofday");
abort();
}
run_body(b, iterations);
rv = gettimeofday(&tv_after, NULL);
if (rv) {
perror("gettimeofday");
abort();
}
tv_after.tv_sec -= tv_before.tv_sec;
time = tv_after.tv_sec * 1E6 + tv_after.tv_usec;
time -= tv_before.tv_usec;
time *= 1000;
return time;
}
#define TRIAL_NSEC 0.3E9
#define TARGET_NSEC 3E9
static double run_benchmark(struct internal_bench *b)
{
long iterations = 128;
double nsec;
while (1) {
nsec = measure_once(b, iterations);
if (nsec > TRIAL_NSEC) {
break;
}
iterations = ((unsigned long)iterations) << 1;
if (iterations <= 0) { // overflow
abort();
}
}
while (nsec < TARGET_NSEC) {
double target_iterations = iterations * TARGET_NSEC * 1.1 / nsec;
if (target_iterations > (double)LONG_MAX) {
abort();
}
iterations = target_iterations;
nsec = measure_once(b, iterations);
}
return nsec / iterations;
}
void report_benchmark(const char *name, bench_body body, uintptr_t param)
{
int i;
struct internal_bench b = {.body = body, .param = param};
for (i = 0; i < 3; i++) {
double nsec = run_benchmark(&b);
int slen;
int padding_size;
slen = printf("Benchmark: %s", name);
if (param && name[strlen(name)-1] != ')') {
slen += printf("(%lld)", (long long)param);
}
padding_size = 60 - slen;
if (padding_size < 1) {
padding_size = 1;
}
printf("%*c%f nsec\n", padding_size, ' ', nsec);
fflush(stdout);
}
}