* (C) 2011 by Argonne National Laboratory.
* See COPYRIGHT in top-level directory.
*/
-/*
+/*
* Test of reduce scatter block with large data on an intercommunicator
* (needed in MPICH to trigger the long-data algorithm)
*
- * Each processor contributes its rank + the index to the reduction,
+ * Each processor contributes its rank + the index to the reduction,
* then receives the ith sum
*
* Can be called with any number of processors.
#include <stdlib.h>
#include "mpitest.h"
-int main( int argc, char **argv )
+int main(int argc, char **argv)
{
- int err = 0;
- int size, rsize, rank, i;
- int recvcount, /* Each process receives this much data */
- sendcount, /* Each process contributes this much data */
- basecount; /* Unit of elements - basecount *rsize is recvcount,
- etc. */
- int isLeftGroup;
+ int err = 0;
+ int size, rsize, rank, i;
+ int recvcount, /* Each process receives this much data */
+ sendcount, /* Each process contributes this much data */
+ basecount; /* Unit of elements - basecount *rsize is recvcount,
+ * etc. */
+ int isLeftGroup;
long long *sendbuf, *recvbuf;
long long sumval;
MPI_Comm comm;
- MTest_Init( &argc, &argv );
+ MTest_Init(&argc, &argv);
comm = MPI_COMM_WORLD;
basecount = 1024;
- while (MTestGetIntercomm( &comm, &isLeftGroup, 2 )) {
- if (comm == MPI_COMM_NULL) continue;
-
- MPI_Comm_remote_size( comm, &rsize );
- MPI_Comm_size( comm, &size );
- MPI_Comm_rank( comm, &rank );
-
- if (0) {
- printf( "[%d] %s (%d,%d) remote %d\n", rank,
- isLeftGroup ? "L" : "R",
- rank, size, rsize );
- }
-
- recvcount = basecount * rsize;
- sendcount = basecount * rsize * size;
-
- sendbuf = (long long *) malloc( sendcount * sizeof(long long) );
- if (!sendbuf) {
- fprintf( stderr, "Could not allocate %d ints for sendbuf\n",
- sendcount );
- MPI_Abort( MPI_COMM_WORLD, 1 );
- }
-
- for (i=0; i<sendcount; i++) {
- sendbuf[i] = (long long)(rank*sendcount + i);
- }
- recvbuf = (long long *)malloc( recvcount * sizeof(long long) );
- if (!recvbuf) {
- fprintf( stderr, "Could not allocate %d ints for recvbuf\n",
- recvcount );
- MPI_Abort( MPI_COMM_WORLD, 1 );
- }
- for (i=0; i<recvcount; i++) {
- recvbuf[i] = (long long)(-i);
- }
-
- MPI_Reduce_scatter_block( sendbuf, recvbuf, recvcount, MPI_LONG_LONG,
- MPI_SUM, comm );
-
- /* Check received data */
- for (i=0; i<recvcount; i++) {
- sumval = (long long)(sendcount) * (long long)((rsize * (rsize-1))/2) +
- (long long)(i + rank * rsize * basecount) * (long long)rsize;
- if (recvbuf[i] != sumval) {
- err++;
- if (err < 4) {
- fprintf( stdout, "Did not get expected value for reduce scatter\n" );
- fprintf( stdout, "[%d] %s recvbuf[%d] = %lld, expected %lld\n",
- rank,
- isLeftGroup ? "L" : "R",
- i, recvbuf[i], sumval );
- }
- }
- }
-
- free(sendbuf);
- free(recvbuf);
-
- MTestFreeComm( &comm );
+ while (MTestGetIntercomm(&comm, &isLeftGroup, 2)) {
+ if (comm == MPI_COMM_NULL)
+ continue;
+
+ MPI_Comm_remote_size(comm, &rsize);
+ MPI_Comm_size(comm, &size);
+ MPI_Comm_rank(comm, &rank);
+
+ if (0) {
+ printf("[%d] %s (%d,%d) remote %d\n", rank, isLeftGroup ? "L" : "R", rank, size, rsize);
+ }
+
+ recvcount = basecount * rsize;
+ sendcount = basecount * rsize * size;
+
+ sendbuf = (long long *) malloc(sendcount * sizeof(long long));
+ if (!sendbuf) {
+ fprintf(stderr, "Could not allocate %d ints for sendbuf\n", sendcount);
+ MPI_Abort(MPI_COMM_WORLD, 1);
+ }
+
+ for (i = 0; i < sendcount; i++) {
+ sendbuf[i] = (long long) (rank * sendcount + i);
+ }
+ recvbuf = (long long *) malloc(recvcount * sizeof(long long));
+ if (!recvbuf) {
+ fprintf(stderr, "Could not allocate %d ints for recvbuf\n", recvcount);
+ MPI_Abort(MPI_COMM_WORLD, 1);
+ }
+ for (i = 0; i < recvcount; i++) {
+ recvbuf[i] = (long long) (-i);
+ }
+
+ MPI_Reduce_scatter_block(sendbuf, recvbuf, recvcount, MPI_LONG_LONG, MPI_SUM, comm);
+
+ /* Check received data */
+ for (i = 0; i < recvcount; i++) {
+ sumval = (long long) (sendcount) * (long long) ((rsize * (rsize - 1)) / 2) +
+ (long long) (i + rank * rsize * basecount) * (long long) rsize;
+ if (recvbuf[i] != sumval) {
+ err++;
+ if (err < 4) {
+ fprintf(stdout, "Did not get expected value for reduce scatter\n");
+ fprintf(stdout, "[%d] %s recvbuf[%d] = %lld, expected %lld\n",
+ rank, isLeftGroup ? "L" : "R", i, recvbuf[i], sumval);
+ }
+ }
+ }
+
+ free(sendbuf);
+ free(recvbuf);
+
+ MTestFreeComm(&comm);
}
- MTest_Finalize( err );
+ MTest_Finalize(err);
- MPI_Finalize( );
+ MPI_Finalize();
return 0;
}
