Open MPI logo

Open MPI User's Mailing List Archives

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

Subject: Re: [OMPI users] open-mpi behaviour on Fedora, Ubuntu, Debian and CentOS
From: Dave Love (d.love_at_[hidden])
Date: 2010-04-27 10:31:23

Gus Correa <gus_at_[hidden]> writes:

> Or run a serial version on the same set of machines,
> compiled in similar ways (compiler version, opt flags, etc)
> to the parallel versions, and compare results.
> If the results don't differ, then you can start blaming MPI.

That wouldn't show that there's actually any OpenMPI-specific problem,
though -- the parallelism potentially introduces indeterminacy. [I
don't mean to imply Guy thinks otherwise, or that anyone has enough
information to guess what's actually happening.] General discussion of
numerical issues and scientific computing war stories must be way
off-topic here...