I talked to Pasha about the change. He suggests fragments are 2-byte aligned to save space. I suspect that on 64-bit platforms the fragment size is already a multiple of 8 bytes so this change will likely only affect 32-bit systems (which is where the bus error is occurring).
-Nathan On Wed, Feb 20, 2013 at 09:39:09PM +0000, Joshua Ladd wrote: > I would hold off, if possible, until I can investigate the issue. I don't, > off-hand, know why the 2-byte alignment, although I would suspect it's for > performance reasons. > > > Josh > > > -----Original Message----- > From: devel-boun...@open-mpi.org [mailto:devel-boun...@open-mpi.org] On > Behalf Of Jeff Squyres (jsquyres) > Sent: Wednesday, February 20, 2013 4:35 PM > To: <de...@open-mpi.org> > Subject: [OMPI devel] openib fragment alignment > Importance: High > > Arrgh. I think you're going to make me eat my words > (http://www.open-mpi.org/community/lists/devel/2013/02/12143.php). > > I just recently lost my access to InfiniBand test gear, so I can't test this > myself. Hypothetically, it should be fine. But throwing in an untested > change literally right before a release without IB vendor say-so really, > really gives me pause... > > Mellanox? > > > On Feb 20, 2013, at 4:27 PM, Open MPI <b...@open-mpi.org> wrote: > > > #3519: Move r28083 to v1.6 branch > > -----------------------------------+-------------------------- > > Reporter: hjelmn | Owner: hjelmn > > Type: changeset move request | Status: new > > Priority: major | Milestone: Open MPI 1.6 > > Version: trunk | > > -----------------------------------+-------------------------- > > (In [28083]) btl/openib: don't align fragments on 2 byte boundaries > > (changed to 8) > > > > cmr:v1.6,v1.7 > > > > -- > > Ticket URL: <https://svn.open-mpi.org/trac/ompi/ticket/3519> > > Open MPI <http://www.open-mpi.org/> > > > > _______________________________________________ > > bugs mailing list > > b...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/bugs > > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel > > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel
