Hi, I would like to start a single process without mpirun and then use MPI_Comm_spawn to start up as many processes as required. I don't want the parent process to take up any resources, so I tried to disconnect the inter communicator and then finalize mpi and exit the parent. But as soon as I do that the children exit too. Why is that? Can I somehow change that behavior? Or can I wait on the children to exit without the waiting taking up CPU time?
The reason I don't need the parent as soon as the children are spawned, is that I need one intra-communicator over all processes. And as far as I know I cannot join the parent and children to one intra-communicator. The purpose of the whole exercise is that I want that my program to use all cores of a node by default when executed without mpirun. I have tested this with OpenMPI 1.4.5. A sample program is here: http://pastebin.com/g2XSZwvY . "Child finalized" is only printed with the sleep(2) in the parent not commented out. Roland -- ORNL/UT Center for Molecular Biophysics cmb.ornl.gov 865-241-1537, ORNL PO BOX 2008 MS6309
