Subject: Re: [OMPI users] Spawn and OpenFabrics
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2009-06-02 12:27:40


On Jun 2, 2009, at 11:37 AM, Allen Barnett wrote:

> std::stringstream ss;
> ss << "partitioner_program " << COMM_WORLD_SIZE;
> system( ss.str().c_str() );
>

You'd probably see the same problem even if you strdup'ed the c_str()
and system()'ed that.

What kernel are you using? Does OMPI say that it has IBV fork support?

     ompi_info --param btl openib --parsable | grep have_fork_support

Be sure to also see http://www.open-mpi.org/faq/?category=openfabrics#ofa-fork
.
> Also, would MPI_COMM_SPAWN suffer from the same difficulties?
>

It shouldn't; we proxy the launch of new commands off to mpirun /
OMPI's run-time system. Specifically: the new process(es) are not
POSIX children of the process(es) that called MPI_COMM_SPAWN.

-- 
Jeff Squyres
Cisco Systems