# hive.lbl.gov
mpirun [-ht] [-v...] [-m method] [-np nprocs] [-args "arglist"] [-machinefile file] [-noenv] exe [args ...]
        -h                      help
        -t                      don't execute any commands
        -v ...                  increase verbosity (MPIRUN_DEBUG)
        -m method               use method rms, slurm, pdsh, ssh or rsh (MPIRUN_METHOD)
        -np nprocs              number of processes to spawn
        -args "arglist"         additional arguments for job launch command
        -machinefile file       machinefile specifying hosts (MPIRUN_MACHINES_FILE)
        -noenv                  disable environment forwarding and local shared memory communication

set MPIRUN_ELANIDMAP_FILE to file listing '<hostname> <elan-netid>' lines, if netids not specified in machinefile
note that files need to be creatable in the current directory