Hi,
I am running a MPI program using cluster and tcp communication.
To run I am using: *mpirun --prefix /usr/local/ --mca btl tcp,self
--hostfile slaves -np 6 scatter*
I am getting following output:
Process 0 on host host1 has elements 0 1 2 3
Process 1 on host host1 has elements 4 5 6 7
Process 2 on host host1 has elements 8 9 10 11
Process 3 on host host1 has elements 12 13 14 15
[slave1][[24708,1],5][btl_tcp_endpoint.c:486:mca_btl_tcp_endpoint_recv_connect_ack]
received unexpected process identifier [[24708,1],4]
When trying to communicate with slave1 i get received unexpected process
identifier error.
My PATH and LD_LIBRARY_PATH are correctly set in .bashrc file.
Source code -
#include <stdlib.h>
#include <stdio.h>
#include "mpi.h"
#define MAXPROC 8 /* Max number of procsses */
#define LENGTH 24 /* length of buffer */
int main(int argc, char* argv[]) {
int i, j, np, me;
const int nametag = 40; /* Tag value for sending name */
const int datatag = 45; /* Tag value for sending data */
const int root = 0; /* Root process in scatter */
MPI_Status status; /* Status object for receive */
char myname[MPI_MAX_PROCESSOR_NAME]; /* Local host name string */
char hostname[MAXPROC][MPI_MAX_PROCESSOR_NAME]; /* Received host names
*/
int namelen;
int x[LENGTH]; /* Send buffer */
int y[LENGTH]; /* Receive buffer */
MPI_Init(&argc, &argv); /* Initialize MPI */
MPI_Comm_size(MPI_COMM_WORLD, &np); /* Get nr of processes */
MPI_Comm_rank(MPI_COMM_WORLD, &me); /* Get own identifier */
MPI_Get_processor_name(myname, &namelen); /* Get host name */
myname[namelen++] = (char)0; /* Terminating null byte */
/* Check that we have an even number of processes and at most MAXPROC */
if (np>MAXPROC || np%2 != 0) {
if (me == 0) {
printf("You have to use an even number of processes (at most %d)\n",
MAXPROC);
}
MPI_Finalize();
exit(0);
}
if (me == 0) { /* Process 0 does this */
/* Initialize the array x with values 0 .. LENGTH-1 */
for (i=0; i<LENGTH; i++) {
x[i] = i;
}
printf("Process %d on host %s is distributing array x to all %d
processes\n\n",
me, myname, np);
/* Scatter the array x to all proceses, place it in y */
MPI_Scatter(x, LENGTH/np, MPI_INT, y, LENGTH/np, MPI_INT, root,
MPI_COMM_WORLD);
/* Print out own portion of the scattered array */
printf("Process %d on host %s has elements", me, myname);
for (i=0; i<LENGTH/np; i++) {
printf(" %d", y[i]);
}
printf("\n");
/* Receive messages with hostname and the scattered data */
/* from all other processes */
for (i=1; i<np; i++) {
MPI_Recv (hostname[i], namelen, MPI_CHAR, i, nametag, MPI_COMM_WORLD,
&status);
MPI_Recv (y, LENGTH/np, MPI_INT, i, datatag, MPI_COMM_WORLD,
&status);
printf("Process %d on host %s has elements", i, hostname[i]);
for (j=0; j<LENGTH/np; j++) {
printf(" %d", y[j]);
}
printf("\n");
}
printf("Ready\n");
} else { /* all other processes do this */
/* Receive the scattered array from process 0, place it in array y */
MPI_Scatter(x, LENGTH/np, MPI_INT, y, LENGTH/np, MPI_INT, root, \
MPI_COMM_WORLD);
/* Send own name back to process 0 */
MPI_Send (myname, namelen, MPI_CHAR, 0, nametag, MPI_COMM_WORLD);
/* Send the received array back to process 0 */
MPI_Send (y, LENGTH/np, MPI_INT, 0, datatag, MPI_COMM_WORLD);
}
MPI_Finalize();
exit(0);
}
Any idea what could be wrong?
Thanks
