xref: /petsc/src/benchmarks/PetscGetCPUTime.c (revision 5f80ce2ab25dff0f4601e710601cbbcecf323266)
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24cd03b37SPatrick Sanan #include <petsctime.h>
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4b620a312SSatish Balay int main(int argc,char **argv)
5b620a312SSatish Balay {
6b0a32e0cSBarry Smith   PetscLogDouble x,y;
7d3093643SSatish Balay   long int       i,j,A[100000],ierr;
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9a438ae71SBarry Smith   ierr = PetscInitialize(&argc,&argv,0,0);if (ierr) return ierr;
10b620a312SSatish Balay   /* To take care of paging effects */
11*5f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscGetCPUTime(&y));
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13b620a312SSatish Balay   for (i=0; i<2; i++) {
14*5f80ce2aSJacob Faibussowitsch     CHKERRQ(PetscGetCPUTime(&x));
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16b620a312SSatish Balay     /*
17b620a312SSatish Balay        Do some work for at least 1 ms. Most CPU timers
18b620a312SSatish Balay        cannot measure anything less than that
19b620a312SSatish Balay      */
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216f2b61bcSKarl Rupp     for (j=0; j<20000*(i+1); j++) A[j]=i+j;
22*5f80ce2aSJacob Faibussowitsch     CHKERRQ(PetscGetCPUTime(&y));
23b4d8b9abSSatish Balay     fprintf(stdout,"%-15s : %e sec\n","PetscGetCPUTime",(y-x)/10.0);
24b620a312SSatish Balay   }
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26f3fe499bSBarry Smith   ierr = PetscFinalize();
2726f47effSBarry Smith   return ierr;
28b620a312SSatish Balay }
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