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This is the simple MPI program:

#include <stdio.h>
#include <mpi.h>
main(int argc, char ** argv)
{
int rank,size;


MPI_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);

if(rank==0)
{
printf("Hello world, I'm process %d of %d and I'm the boss\n",rank,size);}


else{
printf("Hello world, I'm process %d of %d\n",rank,size);
}

MPI_Finalize();
}

THIS IS THE SAME EXACT CODE THE TEACHER USED!

Here are the results I got compiling with:

mpicc hello.c -o hellompi
mpirun -np 8 ./hellompi

Hello world, I'm process 0 of 1 and I'm the boss
Hello world, I'm process 0 of 1 and I'm the boss
Hello world, I'm process 0 of 1 and I'm the boss
Hello world, I'm process 0 of 1 and I'm the boss
Hello world, I'm process 0 of 1 and I'm the boss
Hello world, I'm process 0 of 1 and I'm the boss
Hello world, I'm process 0 of 1 and I'm the boss
Hello world, I'm process 0 of 1 and I'm the boss

Obviously the right code produces:

Hello world, I'm process 0 of 7 and I'm the boss
Hello world, I'm process 1 of 7 
Hello world, I'm process 2 of 7 
Hello world, I'm process 3 of 7 
Hello world, I'm process 4 of 7 
Hello world, I'm process 5 of 7 
Hello world, I'm process 6 of 7 
Hello world, I'm process 7 of 7

So obviously I need to uninstall OpenMPI, MPI then just install the right MPI... How do i do this?

Oh and yes this is what I get when I run:

cat /proc/cpuinfo | grep processor

processor      :0
processor      :1
processor      :2
processor      :3
processor      :4
processor      :5
processor      :6
processor      :7

plus i never get anything different even if when i mpirun -np 2

so i sudo apt-get remove mpi

then it looks like it uninstalls but then i run

mpichversion

and still get a version 3.0.1

bluerubez
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  • possible duplicate of [MPI\_Rank return same process number for all process](http://stackoverflow.com/questions/20287564/mpi-rank-return-same-process-number-for-all-process) – Jonathan Dursi Sep 12 '14 at 11:14

1 Answers1

0

Ok yes i uninstalled OpenMPI and it worked immediately

sudo apt-get remove openmpi-common

I first uninstalled then reinstalled MPI and this did nothing.

bluerubez
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