mpiexec is a direct link to mpiexec.hydra
mpirun is a wrapper script that determines your batch system and simplifies the launch for the user, but eventually also calls mpiexec.hydra
Our site is considering removing the mpiexec link and instead linking it to mpirun. Can you see any possible downside to doing this?
Hi Ronald, the commands mpirun and mpiexec.hydra are interchangeable. You can specify all mpiexec.hydra options with the mpirun command. However, you are recommended to use the mpirun command when an MPI program is running under a batch scheduler or job manager, as the mpirun command detects if the MPI job is submitted from within a session allocated using a job scheduler like PBS Pro* or LSF*. Thanks.