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libs/ck-libs/ampi/romio/test/split_coll.c

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/* -*- Mode: C; c-basic-offset:4 ; -*- */
/*  
 *  (C) 2001 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */
#include "mpi.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>

/* A 32^3 array. For other array sizes, change array_of_gsizes below. */

/* Uses split collective I/O. Writes a 3D block-distributed array to a file
   corresponding to the global array in row-major (C) order, reads it
   back, and checks that the data read is correct. */

/* The file name is taken as a command-line argument. */

/* Note that the file access pattern is noncontiguous. */
   
int main(int argc, char **argv)
{
    MPI_Datatype newtype;
    int i, ndims, array_of_gsizes[3], array_of_distribs[3];
    int order, nprocs, j, len;
    int array_of_dargs[3], array_of_psizes[3];
    int *readbuf, *writebuf, bufcount, mynod, *tmpbuf, array_size;
    int errs=0, toterrs;
    char *filename;
    MPI_File fh;
    MPI_Status status;
    MPI_Request request;

    MPI_Init(&argc,&argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &mynod);
    MPI_Comm_size(MPI_COMM_WORLD, &nprocs);

/* process 0 takes the file name as a command-line argument and 
   broadcasts it to other processes */
    if (!mynod) {
    i = 1;
    while ((i < argc) && strcmp("-fname", *argv)) {
        i++;
        argv++;
    }
    if (i >= argc) {
        fprintf(stderr, "\n*#  Usage: coll_test -fname filename\n\n");
        MPI_Abort(MPI_COMM_WORLD, 1);
    }
    argv++;
    len = strlen(*argv);
    filename = (char *) malloc(len+1);
    strcpy(filename, *argv);
    MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD);
    MPI_Bcast(filename, len+1, MPI_CHAR, 0, MPI_COMM_WORLD);
    }
    else {
    MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD);
    filename = (char *) malloc(len+1);
    MPI_Bcast(filename, len+1, MPI_CHAR, 0, MPI_COMM_WORLD);
    }


/* create the distributed array filetype */
    ndims = 3;
    order = MPI_ORDER_C;

    array_of_gsizes[0] = 32;
    array_of_gsizes[1] = 32;
    array_of_gsizes[2] = 32;

    array_of_distribs[0] = MPI_DISTRIBUTE_BLOCK;
    array_of_distribs[1] = MPI_DISTRIBUTE_BLOCK;
    array_of_distribs[2] = MPI_DISTRIBUTE_BLOCK;

    array_of_dargs[0] = MPI_DISTRIBUTE_DFLT_DARG;
    array_of_dargs[1] = MPI_DISTRIBUTE_DFLT_DARG;
    array_of_dargs[2] = MPI_DISTRIBUTE_DFLT_DARG;

    for (i=0; i<ndims; i++) array_of_psizes[i] = 0;
    MPI_Dims_create(nprocs, ndims, array_of_psizes);

    MPI_Type_create_darray(nprocs, mynod, ndims, array_of_gsizes, 
               array_of_distribs, array_of_dargs,
               array_of_psizes, order, MPI_INT, &newtype);
    MPI_Type_commit(&newtype);

/* initialize writebuf */

    MPI_Type_size(newtype, &bufcount);
    bufcount = bufcount/sizeof(int);
    writebuf = (int *) malloc(bufcount * sizeof(int));
    for (i=0; i<bufcount; i++) writebuf[i] = 1;

    array_size = array_of_gsizes[0]*array_of_gsizes[1]*array_of_gsizes[2];
    tmpbuf = (int *) calloc(array_size, sizeof(int));
    MPI_Irecv(tmpbuf, 1, newtype, mynod, 10, MPI_COMM_WORLD, &request);
    MPI_Send(writebuf, bufcount, MPI_INT, mynod, 10, MPI_COMM_WORLD);
    MPI_Wait(&request, &status);

    j = 0;
    for (i=0; i<array_size; i++)
    if (tmpbuf[i]) {
        writebuf[j] = i;
        j++;
    }
    free(tmpbuf);

    if (j != bufcount) {
    fprintf(stderr, "Error in initializing writebuf on process %d\n", mynod);
    MPI_Abort(MPI_COMM_WORLD, 1);
    }
/* end of initialization */

    /* write the array to the file */
    MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, 
                  MPI_INFO_NULL, &fh);
    MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", MPI_INFO_NULL);
    MPI_File_write_all_begin(fh, writebuf, bufcount, MPI_INT);
    MPI_File_write_all_end(fh, writebuf, &status);
    MPI_File_close(&fh);


    /* now read it back */
    readbuf = (int *) malloc(bufcount * sizeof(int));
    MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, 
                  MPI_INFO_NULL, &fh);
    MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", MPI_INFO_NULL);
    MPI_File_read_all_begin(fh, readbuf, bufcount, MPI_INT);
    MPI_File_read_all_end(fh, readbuf, &status);
    MPI_File_close(&fh);

    /* check the data read */
    for (i=0; i<bufcount; i++) {
    if (readbuf[i] != writebuf[i]) {
        errs++;
        fprintf(stderr, "Process %d, readbuf %d, writebuf %d, i %d\n", 
            mynod, readbuf[i], writebuf[i], i);
    }
    }

    MPI_Allreduce( &errs, &toterrs, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD );
    if (mynod == 0) {
    if( toterrs > 0) {
        fprintf( stderr, "Found %d errors\n", toterrs );
    }
    else {
        fprintf( stdout, " No Errors\n" );
    }
    }

    MPI_Type_free(&newtype);
    free(readbuf);
    free(writebuf);
    free(filename);

    MPI_Finalize();
    return 0;
}

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