Thank you, Gus! I did go through the mpiexec/mpirun man pages but wasn't quite clear that -report-bindings was what I was looking for. So what I did is rerun a program w/ --report-bindings but no bindings were reported.
Scratching my head, I decided to include --bind-to-core as well. Voila, the bindings are reported! Awesome, but now here is my concern. If we have OpenMPI-based applications launched as batch jobs via a batch scheduler like SLURM, PBS, LSF, etc. (which decides the placement of the app and dispatches it to the compute hosts), then will including "--report-bindings --bind-to-core" cause problems? Certainly I can test this, but concerned there may be a case where inclusion of --bind-to-core would cause an unexpected problem I did not account for. --john -----Original Message----- From: users [mailto:users-boun...@open-mpi.org] On Behalf Of Gus Correa Sent: Thursday, March 27, 2014 2:06 PM To: Open MPI Users Subject: Re: [OMPI users] Mapping ranks to hosts (from MPI error messages) Hi John Take a look at the mpiexec/mpirun options: -report-bindings (this one should report what you want) and maybe also also: -bycore, -bysocket, -bind-to-core, -bind-to-socket, ... and similar, if you want more control on where your MPI processes run. "man mpiexec" is your friend! I hope this helps, Gus Correa On 03/27/2014 01:53 PM, Sasso, John (GE Power & Water, Non-GE) wrote: > When a piece of software built against OpenMPI fails, I will see an > error referring to the rank of the MPI task which incurred the failure. > For example: > > MPI_ABORT was invoked on rank 1236 in communicator MPI_COMM_WORLD > > with errorcode 1. > > Unfortunately, I do not have access to the software code, just the > installation directory tree for OpenMPI. My question is: Is there a > flag that can be passed to mpirun, or an environment variable set, > which would reveal the mapping of ranks to the hosts they are on? > > I do understand that one could have multiple MPI ranks running on the > same host, but finding a way to determine which rank ran on what host > would go a long way in help troubleshooting problems which may be > central to the host. Thanks! > > --john > > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > _______________________________________________ users mailing list us...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/users
