Compiling C++ Example Using the LAM/MPI modules

$ cp -r /share/apps/samples/lammpi-c++ ./

First you need to create your source code. See example mpi_hello.cpp  below:

// Filename: mpi_hello.cpp
// Description: A parallel hello world program

#include <iostream>
#include <mpi.h>
#include <stdlib.h>

int main(int argc, char *argv[])
{
        MPI::Init(argc, argv);

        int rank = MPI::COMM_WORLD.Get_rank();
        int size = MPI::COMM_WORLD.Get_size();

        std::cout<<"Returned: "<<system("sleep 2")<<" ";
        std::cout << "Hello World! I am " << rank << " of " << size <<
        std::endl;

        MPI::Finalize();
        return(0);
}

Then you must load the correct lammpi module

$ module load lam-intel (Loads the lammpi/intel-12 module)

$ module load lammpi/intel-11

$ module load lammpi/intel-12

$ module load lammpi/gnu 

$ module load lam-gnu (loads the lammpi/gnu module)

Then compile the code

$ mpiCC -o lam-hello mpi_hello.cpp

Write the jobfile (jobfile.job)

#PBS -N lam-hello
#PBS -q @nic-cluster.mst.edu
#PBS -l nodes=2
#PBS -l walltime=01:00:00
#PBS -m abe
#PBS -M joeminer@mst.edu
#PBS -V
cd $PBS_O_WORKDIR
mpiexec -v -boot -n 2 ./lam-hello

Submit the Job

$ qsub jobfile.job

Output