Controlling node mapping of MPI_COMM_SPAWN

Question

The context:

This whole issue can be summarized that I\'m trying replicate the behaviour of a call to system (or fork), but in an mpi environ

Answer 1

From the Open MPI MPI_Comm_spawn man page

   The following keys for info are recognized in Open MPI. (The reserved values mentioned in Section 5.3.4 of the MPI-2 standard are not implemented.)

   Key                    Type     Description
   ---                    ----     -----------

   host                   char *   Host on which the process should be
                                   spawned.  See the orte_host man
                                   page for an explanation of how this
                                   will be used.

and you can use MPI_Get_processor_name() in order to get the hostname a MPI task is running on.