xref: /petsc/src/benchmarks/MPI_Wtime.c (revision 5b6bfdb9644f185dbf5e5a09b808ec241507e1e7)
1 
2 #include <petscsys.h>
3 
4 int main(int argc,char **argv)
5 {
6   double x,y;
7   int    ierr;
8 
9   ierr = PetscInitialize(&argc,&argv,0,0);if (ierr) return ierr;
10   /* To take care of paging effects */
11   y = MPI_Wtime();
12 
13   x = MPI_Wtime();
14   y = MPI_Wtime();
15   y = MPI_Wtime();
16   y = MPI_Wtime();
17   y = MPI_Wtime();
18   y = MPI_Wtime();
19   y = MPI_Wtime();
20   y = MPI_Wtime();
21   y = MPI_Wtime();
22   y = MPI_Wtime();
23   y = MPI_Wtime();
24 
25   fprintf(stdout,"%-15s : %e sec\n","MPI_Wtime",(y-x)/10.0);
26   y = MPI_Wtick();
27   fprintf(stdout,"%-15s : %e sec\n","MPI_Wtick",y);
28 
29   x    = MPI_Wtime();
30   ierr = PetscSleep(10);CHKERRQ(ierr);
31   y    = MPI_Wtime();
32   fprintf(stdout,"%-15s : %e sec - Slept for 10 sec \n","MPI_Wtime",(y-x));
33 
34   ierr = PetscFinalize();
35   return ierr;
36 }
37