Measure execution time in C++ OpenMP code

Question

I am running a .cpp code (i) in sequential style and (ii) using OpenMP statements. I am trying to see the time difference. For calculating time, I use this:

Answer 1

I've seen clock() reporting CPU time, instead of real time.

You could use

struct timeval start, end;
gettimeofday(&start, NULL);

// benchmark code

gettimeofday(&end, NULL);

delta = ((end.tv_sec  - start.tv_sec) * 1000000u + 
         end.tv_usec - start.tv_usec) / 1.e6;

To time things instead