/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
* (C) 2001 by Argonne National Laboratory.
* See COPYRIGHT in top-level directory.
*/
#include "mpi.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
/* tests noncontiguous reads/writes using independent I/O */
#define SIZE 5000
#define VERBOSE 0
static void handle_error(int errcode, const char *str)
{
char msg[MPI_MAX_ERROR_STRING];
int resultlen;
MPI_Error_string(errcode, msg, &resultlen);
fprintf(stderr, "%s: %s\n", str, msg);
MPI_Abort(MPI_COMM_WORLD, 1);
}
#define MPI_CHECK(fn) { int errcode; errcode = (fn); if (errcode != MPI_SUCCESS) handle_error(errcode, #fn); }
int main(int argc, char **argv)
{
int *buf, i, mynod, nprocs, len, b[3];
int errs = 0, toterrs;
MPI_Aint d[3];
MPI_File fh;
MPI_Status status;
char *filename;
MPI_Datatype typevec, newtype, t[3];
MPI_Info info;
MPI_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
MPI_Comm_rank(MPI_COMM_WORLD, &mynod);
if (nprocs != 2) {
fprintf(stderr, "Run this program on two processes\n");
MPI_Abort(MPI_COMM_WORLD, 1);
}
/* process 0 takes the file name as a command-line argument and
broadcasts it to other processes (length first, then string) */
if (!mynod) {
i = 1;
while ((i < argc) && strcmp("-fname", *argv)) {
i++;
argv++;
}
if (i >= argc) {
fprintf(stderr, "\n*# Usage: noncontig -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);
}
buf = (int *) malloc(SIZE * sizeof(int));
MPI_Type_vector(SIZE / 2, 1, 2, MPI_INT, &typevec);
/* create a struct type with explicitly set LB and UB; displacements
* of typevec are such that the types for the two processes won't
* overlap.
*/
b[0] = b[1] = b[2] = 1;
d[0] = 0;
d[1] = mynod * sizeof(int);
d[2] = SIZE * sizeof(int);
t[0] = MPI_LB;
t[1] = typevec;
t[2] = MPI_UB;
/* keep the struct, ditch the vector */
MPI_Type_struct(3, b, d, t, &newtype);
MPI_Type_commit(&newtype);
MPI_Type_free(&typevec);
MPI_Info_create(&info);
/* I am setting these info values for testing purposes only. It is
* better to use the default values in practice. */
MPI_Info_set(info, "ind_rd_buffer_size", "1209");
MPI_Info_set(info, "ind_wr_buffer_size", "1107");
if (!mynod) {
#if VERBOSE
fprintf(stderr,
"\ntesting noncontiguous in memory, noncontiguous in file using independent I/O\n");
#endif
MPI_File_delete(filename, MPI_INFO_NULL);
}
MPI_Barrier(MPI_COMM_WORLD);
MPI_CHECK(MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, info, &fh));
/* set the file view for each process -- now writes go into the non-
* overlapping but interleaved region defined by the struct type up above
*/
MPI_CHECK(MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", info));
/* fill our buffer with a pattern and write, using our type again */
for (i = 0; i < SIZE; i++)
buf[i] = i + mynod * SIZE;
MPI_CHECK(MPI_File_write(fh, buf, 1, newtype, &status));
MPI_Barrier(MPI_COMM_WORLD);
/* fill the entire buffer with -1's. read back with type.
* note that the result of this read should be that every other value
* in the buffer is still -1, as defined by our type.
*/
for (i = 0; i < SIZE; i++)
buf[i] = -1;
MPI_CHECK(MPI_File_read_at(fh, 0, buf, 1, newtype, &status));
/* check that all the values read are correct and also that we didn't
* overwrite any of the -1 values that we shouldn't have.
*/
for (i = 0; i < SIZE; i++) {
if (!mynod) {
if ((i % 2) && (buf[i] != -1)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be -1\n", mynod, i, buf[i]);
}
if (!(i % 2) && (buf[i] != i)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be %d\n", mynod, i, buf[i], i);
}
} else {
if ((i % 2) && (buf[i] != i + mynod * SIZE)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be %d\n",
mynod, i, buf[i], i + mynod * SIZE);
}
if (!(i % 2) && (buf[i] != -1)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be -1\n", mynod, i, buf[i]);
}
}
}
MPI_CHECK(MPI_File_close(&fh));
MPI_Barrier(MPI_COMM_WORLD);
if (!mynod) {
#if VERBOSE
fprintf(stderr,
"\ntesting noncontiguous in memory, contiguous in file using independent I/O\n");
#endif
MPI_File_delete(filename, MPI_INFO_NULL);
}
MPI_Barrier(MPI_COMM_WORLD);
MPI_CHECK(MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, info, &fh));
/* in this case we write to either the first half or the second half
* of the file space, so the regions are not interleaved. this is done
* by leaving the file view at its default.
*/
for (i = 0; i < SIZE; i++)
buf[i] = i + mynod * SIZE;
MPI_CHECK(MPI_File_write_at(fh, mynod * (SIZE / 2) * sizeof(int), buf, 1, newtype, &status));
MPI_Barrier(MPI_COMM_WORLD);
/* same as before; fill buffer with -1's and then read; every other
* value should still be -1 after the read
*/
for (i = 0; i < SIZE; i++)
buf[i] = -1;
MPI_CHECK(MPI_File_read_at(fh, mynod * (SIZE / 2) * sizeof(int), buf, 1, newtype, &status));
/* verify that the buffer looks like it should */
for (i = 0; i < SIZE; i++) {
if (!mynod) {
if ((i % 2) && (buf[i] != -1)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be -1\n", mynod, i, buf[i]);
}
if (!(i % 2) && (buf[i] != i)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be %d\n", mynod, i, buf[i], i);
}
} else {
if ((i % 2) && (buf[i] != i + mynod * SIZE)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be %d\n",
mynod, i, buf[i], i + mynod * SIZE);
}
if (!(i % 2) && (buf[i] != -1)) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be -1\n", mynod, i, buf[i]);
}
}
}
MPI_CHECK(MPI_File_close(&fh));
MPI_Barrier(MPI_COMM_WORLD);
if (!mynod) {
#if VERBOSE
fprintf(stderr,
"\ntesting contiguous in memory, noncontiguous in file using independent I/O\n");
#endif
MPI_File_delete(filename, MPI_INFO_NULL);
}
MPI_Barrier(MPI_COMM_WORLD);
MPI_CHECK(MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, info, &fh));
/* set the file view so that we have interleaved access again */
MPI_CHECK(MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", info));
/* this time write a contiguous buffer */
for (i = 0; i < SIZE; i++)
buf[i] = i + mynod * SIZE;
MPI_CHECK(MPI_File_write(fh, buf, SIZE, MPI_INT, &status));
MPI_Barrier(MPI_COMM_WORLD);
/* fill buffer with -1's; this time they will all be overwritten */
for (i = 0; i < SIZE; i++)
buf[i] = -1;
MPI_CHECK(MPI_File_read_at(fh, 0, buf, SIZE, MPI_INT, &status));
for (i = 0; i < SIZE; i++) {
if (!mynod) {
if (buf[i] != i) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be %d\n", mynod, i, buf[i], i);
}
} else {
if (buf[i] != i + mynod * SIZE) {
errs++;
fprintf(stderr, "Process %d: buf %d is %d, should be %d\n",
mynod, i, buf[i], i + mynod * SIZE);
}
}
}
MPI_CHECK(MPI_File_close(&fh));
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);
MPI_Info_free(&info);
free(buf);
free(filename);
MPI_Finalize();
return 0;
}