/*
* (C) 2017 by Argonne National Laboratory.
* See COPYRIGHT in top-level directory.
*
* Portions of this code were written by Intel Corporation.
* Copyright (C) 2011-2017 Intel Corporation. Intel provides this material
* to Argonne National Laboratory subject to Software Grant and Corporate
* Contributor License Agreement dated February 8, 2012.
*
* This program checks if MPICH can correctly handle a huge message receive
* when the sender underflows by sending a much smaller message
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <memory.h>
#include <mpi.h>
#include "mpitest.h"
#define HUGE_SIZE (10*1024*1024)
int main(int argc, char *argv[])
{
int size, rank;
int dest;
char *buff;
MTest_Init(&argc, &argv);
buff = malloc(HUGE_SIZE);
buff[0] = 0;
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
dest = size - 1;
/* Try testing underflow to make sure things work if we try to send 1 byte
* when receiving a huge message */
if (rank == 0) {
MPI_Send(buff, 1, MPI_BYTE, dest, 0, MPI_COMM_WORLD);
} else if (rank == dest) {
MPI_Recv(buff, HUGE_SIZE, MPI_BYTE, 0, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
}
free(buff);
MPI_Barrier(MPI_COMM_WORLD);
MTest_Finalize(0);
return 0;
}