Both Open MPI 2 and Open MPI 3 are available on development and compute nodes. Either version must be called via the module
command. The most important thing about using Open MPI is to be sure to run with the same Open MPI module version that was used to compile the MPI code. In other words, if you compiled a program with mpicc
using Open MPI 2, then you must load the Open MPI 2 version before you invoke the program with mpirun
.
module load mpi/openmpi-x86_64
mpirun name_of_program
module load mpi/openmpi3-x86_64
mpirun name_of_program
For more information about the module
command see ‘Software Modules’.