xref: /petsc/src/benchmarks/PetscGetCPUTime.c (revision abdd934af67c1cc360c4d0cfcf2de16e188d627e)

#include <petsctime.h>

int main(int argc, char **argv)
{
  PetscLogDouble x, y;
  long int       i, j, A[100000], ierr;

  PetscCall(PetscInitialize(&argc, &argv, 0, 0));
  /* To take care of paging effects */
  PetscCall(PetscGetCPUTime(&y));

  for (i = 0; i < 2; i++) {
    PetscCall(PetscGetCPUTime(&x));

    /*
       Do some work for at least 1 ms. Most CPU timers
       cannot measure anything less than that
     */

    for (j = 0; j < 20000 * (i + 1); j++) A[j] = i + j;
    PetscCall(PetscGetCPUTime(&y));
    fprintf(stdout, "%-15s : %e sec\n", "PetscGetCPUTime", (y - x) / 10.0);
  }

  PetscCall(PetscFinalize());
  return 0;
}