Hello, the following code exposes a problem we are experiencing with our OpenMPI 1.6.[24] installations.
My colleague Moritz Hanke isolated the problem to an interaction of MPI_Type_create_struct with a previous MPI_Type_dup. When MPI_Type_dup on line 67 of the example is replaced with a straight assignment of MPI_INT to sends[0], the problem goes away. We are using a patched version of OpenMPI which includes the changes from r28319. Regards, Thomas Jahns -- Thomas Jahns DKRZ GmbH, Department: Application software Deutsches Klimarechenzentrum Bundesstraße 45a D-20146 Hamburg Phone: +49-40-460094-151 Fax: +49-40-460094-270 Email: Thomas Jahns <ja...@dkrz.de>
#include <mpi.h>
#include <stdio.h>
/**
* usage:
mpicc -std=gnu99 mpi_test.c && a.out
* expected output:
first test:
second test:
third test:
* actual output
first test:
second test:
recv_data[0] = 131072
ref_recv_data[0] = 0
recv_data[1] = -65536
ref_recv_data[1] = 2
third test:
*/
void do_test(MPI_Datatype * sends, int ref_recv_data[2]);
int main(void) {
MPI_Init(NULL, NULL);
int rank, size;
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
if (size == 1) {
{
MPI_Datatype sends[2];
{
sends[0] = MPI_INT;
}
{
int count = 1;
int blocklength = 1;
int array_of_displacements[] = {2};
MPI_Type_create_indexed_block(count, blocklength, array_of_displacements,
MPI_INT, &sends[1]);
MPI_Type_commit(&sends[1]);
}
int ref_recv_data[2] = {0, 2};
puts("first test:");
do_test(sends, ref_recv_data);
MPI_Type_free(&sends[1]);
}
{
MPI_Datatype sends[2];
{
MPI_Type_dup(MPI_INT, &sends[0]);
// by definition of MPI_Type_dup no MPI_Type_commit is required
}
{
int count = 1;
int blocklength = 1;
int array_of_displacements[] = {2};
MPI_Type_create_indexed_block(count, blocklength, array_of_displacements,
MPI_INT, &sends[1]);
MPI_Type_commit(&sends[1]);
}
int ref_recv_data[2] = {0, 2};
puts("second test:");
do_test(sends, ref_recv_data);
MPI_Type_free(&sends[1]);
MPI_Type_free(&sends[0]);
}
{
MPI_Datatype sends[2];
{
MPI_Type_dup(MPI_INT, &sends[0]);
// by definition of MPI_Type_dup no MPI_Type_commit is required
}
{
int count = 1;
int blocklength = 1;
int array_of_displacements[] = {1};
MPI_Type_create_indexed_block(count, blocklength, array_of_displacements,
MPI_INT, &sends[1]);
MPI_Type_commit(&sends[1]);
}
int ref_recv_data[2] = {0, 1};
puts("third test:");
do_test(sends, ref_recv_data);
MPI_Type_free(&sends[1]);
MPI_Type_free(&sends[0]);
}
}
MPI_Finalize();
return 0;
}
void do_test(MPI_Datatype * sends, int ref_recv_data[2]) {
MPI_Datatype send_dt;
{
int count = 2;
int array_of_blocklengths[] = {1, 1};
MPI_Aint array_of_displacements[] = {0, 0};
MPI_Type_create_struct(count, array_of_blocklengths, array_of_displacements,
sends, &send_dt);
MPI_Type_commit(&send_dt);
}
int send_data[3] = {0,1,2};
int recv_data[2] = {-1,-1};
MPI_Request request;
MPI_Irecv(recv_data, 2, MPI_INT, 0, 0, MPI_COMM_WORLD, &request);
MPI_Send(send_data, 1, send_dt, 0, 0, MPI_COMM_WORLD);
MPI_Waitall(1, &request, MPI_STATUSES_IGNORE);
MPI_Type_free(&send_dt);
for (int i = 0; i < sizeof(ref_recv_data) / sizeof(ref_recv_data[0]); ++i) {
if (recv_data[i] != ref_recv_data[i])
printf("recv_data[%d] = %d\n"
"ref_recv_data[%d] = %d\n",
i, recv_data[i], i, ref_recv_data[i]);
}
}
smime.p7s
Description: S/MIME Cryptographic Signature
