properly implement BenchTimer on POSIX

(may require a platform check for the clock name on non-linux platforms)
This commit is contained in:
Benoit Jacob 2009-10-29 15:47:56 -04:00
parent d0562bd473
commit a2268ca6b3

View File

@ -2,7 +2,7 @@
// for linear algebra. // for linear algebra.
// //
// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr> // Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com> // Copyright (C) 2009 Benoit Jacob <jacob.benoit.1@gmail.com>
// //
// Eigen is free software; you can redistribute it and/or // Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public // modify it under the terms of the GNU Lesser General Public
@ -27,7 +27,7 @@
#define EIGEN_BENCH_TIMER_H #define EIGEN_BENCH_TIMER_H
#ifndef WIN32 #ifndef WIN32
#include <sys/time.h> #include <time.h>
#include <unistd.h> #include <unistd.h>
#else #else
#define NOMINMAX #define NOMINMAX
@ -41,6 +41,11 @@ namespace Eigen
{ {
/** Elapsed time timer keeping the best try. /** Elapsed time timer keeping the best try.
*
* On POSIX platforms we use clock_gettime with CLOCK_PROCESS_CPUTIME_ID.
* On Windows we use QueryPerformanceCounter
*
* Important: on linux, you must link with -lrt
*/ */
class BenchTimer class BenchTimer
{ {
@ -83,10 +88,9 @@ public:
QueryPerformanceCounter(&query_ticks); QueryPerformanceCounter(&query_ticks);
return query_ticks.QuadPart/m_frequency; return query_ticks.QuadPart/m_frequency;
#else #else
struct timeval tv; timespec ts;
struct timezone tz; clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
gettimeofday(&tv, &tz); return double(ts.tv_sec) + 1e-9 * double(ts.tv_nsec);
return (double)tv.tv_sec + 1.e-6 * (double)tv.tv_usec;
#endif #endif
} }