Setting Up MPI on Aurora at Smith

--D. Thiebaut (talk) 21:18, 4 March 2017 (EST)

---

This page presents the few steps required to setup MPI on a student account on Aurora.

Setting up Bash as Default and Adding MPI to Path

• Login to your 352 account
• Using emacs, add these three lines at the end of your .login file:

if (-x /bin/bash) then
   exec /bin/bash -l
endif 

• Using emacs, add the following lines at the end of your .bash_profile file:

PATH=/Users/classes/352b/bin/mpi/bin:$PATH:$HOME/bin

• When done, logout and log back in.
• Verify that MPI is now in the path and ready to run:

mpicc -v

You should get a long output of information Using built-in specs.

COLLECT_GCC=/usr/bin/gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.8/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.8.4-2ubuntu1~14.04.1'  
...
 --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04.1) 

Testing

• Using emacs, create this simple C program:

/* C Example */
#include <stdio.h>
#include <mpi.h>


int main (argc, argv)
     int argc;
     char *argv[];
{
  int rank, size;

  MPI_Init (&argc, &argv);      /* starts MPI */
  MPI_Comm_rank (MPI_COMM_WORLD, &rank);        /* get current process id */
  MPI_Comm_size (MPI_COMM_WORLD, &size);        /* get number of processes */
  printf( "Hello world from process %d of %d\n", rank, size );
  MPI_Finalize();
  return 0;
}

• Compile and run the program for 2 Processors:

mpicc helloWorld.c -o hello
mpirun -np 2 ./hello

• You should get this output:

Hello world from process 0 of 2
Hello world from process 1 of 2