For pure MPI programs, the mpiexec_mpt launcher automatically pins MPI processes to CPU cores. This ensures that processes do not migrate between the CPUs on a node during a run and results in better performance.
The omplace command is an HPE wrapper script for use with multithreaded MPI programs. Used in conjunction with the mpiexec_mpt launcher, the omplace script pins processes and threads to the CPUs and ensures optimal memory locality and performance.
Put the omplace command between the mpiexec_mpt command and your executable, as in this example.
mpiexec_mpt omplace ./a.out