Actual source code: PetscMalloc.c
petsc-3.7.1 2016-05-15
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      2: #include <petscsys.h>
      3: #include <petsctime.h>

      7: int main(int argc,char **argv)
      8: {
      9:   PetscLogDouble x,y;
     10:   double         value;
     11:   void           *arr[1000],*dummy;
     12:   int            ierr,i,rand1[1000],rand2[1000];
     13:   PetscRandom    r;
     14:   PetscBool      flg;

     16:   PetscInitialize(&argc,&argv,0,0);

     18:   PetscRandomCreate(PETSC_COMM_SELF,&r);
     19:   PetscRandomSetFromOptions(r);
     20:   for (i=0; i<1000; i++) {
     21:     PetscRandomGetValue(r,&value);
     22:     rand1[i] = (int)(value* 144327);
     23:     PetscRandomGetValue(r,&value);
     24:     rand2[i] = (int)(value* 144327);
     25:   }

     27:   /* Take care of paging effects */
     28:   PetscMalloc(100,&dummy);
     29:   PetscFree(dummy);
     30:   PetscTime(&x);

     32:   /* Do all mallocs */
     33:   for (i=0; i< 1000; i++) {
     34:     PetscMalloc(rand1[i],&arr[i]);
     35:   }

     37:   PetscTime(&x);

     39:   /* Do some frees */
     40:   for (i=0; i< 1000; i+=2) {
     41:     PetscFree(arr[i]);
     42:   }

     44:   /* Do some mallocs */
     45:   for (i=0; i< 1000; i+=2) {
     46:     PetscMalloc(rand2[i],&arr[i]);
     47:   }
     48:   PetscTime(&y);

     50:   for (i=0; i< 1000; i++) {
     51:     PetscFree(arr[i]);
     52:   }

     54:   fprintf(stdout,"%-15s : %e sec, with options : ","PetscMalloc",(y-x)/500.0);
     55:   PetscOptionsHasName(NULL,"-malloc",&flg);
     56:   if (flg) fprintf(stdout,"-malloc ");
     57:   fprintf(stdout,"\n");

     59:   PetscRandomDestroy(&r);
     60:   PetscFinalize();
     61:   return(0);
     62: }