#include <petscsys.h>
#include <petsctime.h>

int main(int argc, char **argv)
{
  PetscLogDouble x, y, z;
  PetscScalar    A[10000];

  PetscCall(PetscInitialize(&argc, &argv, 0, 0));
  /* To take care of paging effects */
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscTime(&x));

  PetscCall(PetscTime(&x));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 10000));
  PetscCall(PetscTime(&y));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscMemzero(A, sizeof(PetscScalar) * 0));
  PetscCall(PetscTime(&z));

  fprintf(stdout, "%s : \n", "PetscMemzero");
  fprintf(stdout, "    %-15s : %e sec\n", "Latency", (z - y) / 10.0);
  fprintf(stdout, "    %-15s : %e sec\n", "Per PetscScalar", (2 * y - x - z) / 100000.0);

  PetscCall(PetscFinalize());
  return 0;
}