Actual source code: PetscMemzero.c
petsc-3.8.4 2018-03-24
2: #include <petscsys.h>
3: #include <petsctime.h>
5: int main(int argc,char **argv)
6: {
7: PetscLogDouble x,y,z;
8: PetscScalar A[10000];
11: PetscInitialize(&argc,&argv,0,0);if (ierr) return ierr;
12: /* To take care of paging effects */
13: PetscMemzero(A,sizeof(PetscScalar)*0);
14: PetscTime(&x);
16: PetscTime(&x);
17: PetscMemzero(A,sizeof(PetscScalar)*10000);
18: PetscMemzero(A,sizeof(PetscScalar)*10000);
19: PetscMemzero(A,sizeof(PetscScalar)*10000);
20: PetscMemzero(A,sizeof(PetscScalar)*10000);
21: PetscMemzero(A,sizeof(PetscScalar)*10000);
22: PetscMemzero(A,sizeof(PetscScalar)*10000);
23: PetscMemzero(A,sizeof(PetscScalar)*10000);
24: PetscMemzero(A,sizeof(PetscScalar)*10000);
25: PetscMemzero(A,sizeof(PetscScalar)*10000);
26: PetscMemzero(A,sizeof(PetscScalar)*10000);
27: PetscTime(&y);
28: PetscMemzero(A,sizeof(PetscScalar)*0);
29: PetscMemzero(A,sizeof(PetscScalar)*0);
30: PetscMemzero(A,sizeof(PetscScalar)*0);
31: PetscMemzero(A,sizeof(PetscScalar)*0);
32: PetscMemzero(A,sizeof(PetscScalar)*0);
33: PetscMemzero(A,sizeof(PetscScalar)*0);
34: PetscMemzero(A,sizeof(PetscScalar)*0);
35: PetscMemzero(A,sizeof(PetscScalar)*0);
36: PetscMemzero(A,sizeof(PetscScalar)*0);
37: PetscMemzero(A,sizeof(PetscScalar)*0);
38: PetscTime(&z);
40: fprintf(stdout,"%s : \n","PetscMemzero");
41: fprintf(stdout," %-15s : %e sec\n","Latency",(z-y)/10.0);
42: fprintf(stdout," %-15s : %e sec\n","Per PetscScalar",(2*y-x-z)/100000.0);
44: PetscFinalize();
45: return ierr;
46: }