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QuestionEstimate time of execution c-function execution Pin
CodingStyle7-Jul-15 6:08
memberCodingStyle7-Jul-15 6:08 
Hello all!
I need help. I need to estimate function execution time in under Linux OS. I guess that it's right way to estimate code/algorithm performance.

I'm trying, something like this:
#include <time.h>
#include <sys/time.h>
#include <stdio.h>
void test(){
	int i;int s=0;

	for(i=1; i<1000000; i++){s+=sin(i)/i;}
}
float timedifference_msec(struct timeval t0, struct timeval t1)
{
    return (t1.tv_sec - t0.tv_sec) * 1000.0f + (t1.tv_usec - t0.tv_usec) / 1000.0f;
}

int main(void)
{
	struct timeval t0;
	struct timeval t1;
	float elapsed;
	gettimeofday(&t0, 0);
	f1();
	gettimeofday(&t1, 0);
	elapsed = timedifference_msec(t0, t1);
	printf("Code executed in %f milliseconds.\n", elapsed);
	return 0;
}

. But It's wall clock, I'm not sure that I can estimate performance by this way, besides, I need approach which will allow to measure time of each function which I choose. I've heard that there is approach to use CPU-time.
AnswerRe: Estimate time of execution c-function execution Pin
Richard MacCutchan7-Jul-15 7:31
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