Fix public issue #30: Stop using gettimeofday() altogether on Win32,
as MSVC doesn't include it. Replace with QueryPerformanceCounter(),
which is monotonic and probably reasonably high-resolution.
(Some machines have traditionally had bugs in QPC, but they should
be relatively rare these days, and there's really no much better
alternative that I know of.)
R=csilvers
DELTA=74 (55 added, 19 deleted, 0 changed)
Revision created by MOE tool push_codebase.
MOE_MIGRATION=1556
git-svn-id: https://snappy.googlecode.com/svn/trunk@31 03e5f5b5-db94-4691-08a0-1a8bf15f6143
diff --git a/snappy-test.cc b/snappy-test.cc
index b608516..c9aae2e 100644
--- a/snappy-test.cc
+++ b/snappy-test.cc
@@ -74,21 +74,22 @@
benchmark_cpu_time_us = 0;
}
-struct timeval benchmark_start_real;
-
#ifdef WIN32
+LARGE_INTEGER benchmark_start_real;
FILETIME benchmark_start_cpu;
#else // WIN32
+struct timeval benchmark_start_real;
struct rusage benchmark_start_cpu;
#endif // WIN32
void StartBenchmarkTiming() {
- gettimeofday(&benchmark_start_real, NULL);
#ifdef WIN32
+ QueryPerformanceCounter(&benchmark_start_real);
FILETIME dummy;
CHECK(GetProcessTimes(
GetCurrentProcess(), &dummy, &dummy, &dummy, &benchmark_start_cpu));
#else
+ gettimeofday(&benchmark_start_real, NULL);
if (getrusage(RUSAGE_SELF, &benchmark_start_cpu) == -1) {
perror("getrusage(RUSAGE_SELF)");
exit(1);
@@ -101,14 +102,18 @@
if (!benchmark_running) {
return;
}
- struct timeval benchmark_stop_real;
- gettimeofday(&benchmark_stop_real, NULL);
- benchmark_real_time_us +=
- 1000000 * (benchmark_stop_real.tv_sec - benchmark_start_real.tv_sec);
- benchmark_real_time_us +=
- (benchmark_stop_real.tv_usec - benchmark_start_real.tv_usec);
#ifdef WIN32
+ LARGE_INTEGER benchmark_stop_real;
+ LARGE_INTEGER benchmark_frequency;
+ QueryPerformanceCounter(&benchmark_stop_real);
+ QueryPerformanceFrequency(&benchmark_frequency);
+
+ double elapsed_real = static_cast<double>(
+ benchmark_stop_real.QuadPart - benchmark_start_real.QuadPart) /
+ benchmark_frequency.QuadPart;
+ benchmark_real_time_us += elapsed_real * 1e6 + 0.5;
+
FILETIME benchmark_stop_cpu, dummy;
CHECK(GetProcessTimes(
GetCurrentProcess(), &dummy, &dummy, &dummy, &benchmark_stop_cpu));
@@ -124,6 +129,13 @@
benchmark_cpu_time_us +=
(stop_ulargeint.QuadPart - start_ulargeint.QuadPart + 5) / 10;
#else // WIN32
+ struct timeval benchmark_stop_real;
+ gettimeofday(&benchmark_stop_real, NULL);
+ benchmark_real_time_us +=
+ 1000000 * (benchmark_stop_real.tv_sec - benchmark_start_real.tv_sec);
+ benchmark_real_time_us +=
+ (benchmark_stop_real.tv_usec - benchmark_start_real.tv_usec);
+
struct rusage benchmark_stop_cpu;
if (getrusage(RUSAGE_SELF, &benchmark_stop_cpu) == -1) {
perror("getrusage(RUSAGE_SELF)");
diff --git a/snappy-test.h b/snappy-test.h
index 18f5b1b..649f26e 100644
--- a/snappy-test.h
+++ b/snappy-test.h
@@ -46,6 +46,11 @@
#include <sys/time.h>
+#ifdef HAVE_WINDOWS_H
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#endif
+
#include <string>
#ifdef HAVE_GTEST
@@ -241,15 +246,30 @@
CycleTimer() : real_time_us_(0) {}
void Start() {
+#ifdef WIN32
+ QueryPerformanceCounter(&start_);
+#else
gettimeofday(&start_, NULL);
+#endif
}
void Stop() {
+#ifdef WIN32
+ LARGE_INTEGER stop;
+ LARGE_INTEGER frequency;
+ QueryPerformanceCounter(&stop);
+ QueryPerformanceFrequency(&frequency);
+
+ double elapsed = static_cast<double>(stop.QuadPart - start_.QuadPart) /
+ frequency.QuadPart;
+ real_time_us_ += elapsed * 1e6 + 0.5;
+#else
struct timeval stop;
gettimeofday(&stop, NULL);
real_time_us_ += 1000000 * (stop.tv_sec - start_.tv_sec);
real_time_us_ += (stop.tv_usec - start_.tv_usec);
+#endif
}
double Get() {
@@ -258,7 +278,11 @@
private:
int64 real_time_us_;
+#ifdef WIN32
+ LARGE_INTEGER start_;
+#else
struct timeval start_;
+#endif
};
// Minimalistic microbenchmark framework.
