Type = File path

Default = n/a

This is an advanced MPI parameter. The MPIMACHF parameter defines the given file path as an argument for the -machinefile option of mpiexec. The machine file contains a list of hosts and optionally the number of processes to run on each host. The user needs to specify MPICORES with this parameter or only a single process will be launched and run on the first host machine listed in the file. If the user wishes to run a single process on each node (in which case all other cores on the node could be left available for use with the NCORES parameter) then the machine file would take the form of Figure 7. Alternatively, if the user wished to assign a specific number of processes to launch on each node, the machine file would take the form of Figure 8. This parameter has no default value.

Figure 7: Example machine file to use with the MPIMACHF parameter defining the -machinefile argument of mpiexec. This machine file instructs mpiexec to launch a single process on machines host1, host2, ..., hostN. Each process represents an instance of the Analyst Drive program being run for a single user class.

Figure 8: Example machine file to use with the MPIMACHF parameter defining the -machinefile argument of mpiexec. This machine file instructs mpiexec to launch two processes on machines host1, host2, ..., hostN. Each process represents an instance of the Analyst Drive program being run for a single user class.