Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: [OMPI users] Environment variables [documentation]
From: Paul Kapinos (kapinos_at_[hidden])
Date: 2012-02-27 06:42:57


Dear Open MPI developer,
here:
http://www.open-mpi.org/faq/?category=running#mpi-environmental-variables
are enlisted four envvars Open MPI set for every process. We use they for some
scripting and thank you for providing they.

But simple "mpiexec -np 1 env | grep OMPI" brings lotz more envvars. These are
interesting for us:

1) OMPI_COMM_WORLD_LOCAL_SIZE - seem to contain the number of processes which
are running on the specific node, see also
http://www.open-mpi.org/community/lists/users/2008/07/6054.php

Is this envvar also "stable" as OMPI_COMM_WORLD_LOCAL_RANK is? (This would make
sense as it looks like the OMPI_COMM_WORLD_SIZE, OMPI_COMM_WORLD_RANK pair.)

If yes, maybe it also should be documented in the Wiki page.

2) OMPI_COMM_WORLD_NODE_RANK - is that just a double of
OMPI_COMM_WORLD_LOCAL_RANK ?

Best wishes,
Paul Kapinos

-- 
Dipl.-Inform. Paul Kapinos   -   High Performance Computing,
RWTH Aachen University, Center for Computing and Communication
Seffenter Weg 23,  D 52074  Aachen (Germany)
Tel: +49 241/80-24915