I have some ideas on how to make sure self is always selected. PR coming shortly.
-Nathan On Mon, Mar 21, 2016 at 02:33:53PM +0000, Jeff Squyres (jsquyres) wrote: > On Mar 19, 2016, at 11:53 AM, dpchoudh . <dpcho...@gmail.com> wrote: > > > > 1. Why 'self' needs to be explicitly mentioned when using the BTL > > communication? Since it must always be there for MPI communication to work, > > should it not be implicit? I am sure there is some architectural rationale > > behind this; could someone please elaborate? > > The original intent: it's actually meant to be a BTL, just like any other. > In that sense, if you list an "include" list of BTLs, it needs to be listed > -- just like any other. > > That being said, you're right -- it *is* a little silly these days to have to > explicitly list "self" because no other component has ever replaced it for > process-loopback communication. It might not be too hard to update > mca_btl_base_select() to automatically add "self" to the "include" list, if > it wasn't explicitly mentioned...? > > Want to submit a PR? :-) > > > 2. Why is this (using 'self') not needed when using MTL communication? > > BTLs and MTLs are exclusive. Specifically, see > https://github.com/open-mpi/ompi/blob/master/README#L590-L628. > > > 3. Is it possible to mix BTL and MTL on a single OMPI job? > > By design, no. > > The cm PML was designed to select exactly one MTL for use, as opposed to the > ob1 PML, which was designed to select multiple BTLs for use. > > > For example, if I have a card, let's say Texas Instruments Hyperlink, that > > is only available as BTL, and I also have Qlogic cards on the same nodes, > > can I use something like this: > > > > mpirun -np 3 -H h1,h2,h3 -mca MTL psm -mca BTL self,hlink > > > > 4. If the above answer is yes, then would OpenMPI use both cards > > *simultaneously* (and stripe messages) or would it use the one with higher > > exclusivity and put the other as standby for failure recovery? > > > > Thanks in advance > > Durga > > > > Life is complex. It has real and imaginary parts. > > _______________________________________________ > > users mailing list > > us...@open-mpi.org > > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users > > Link to this post: > > http://www.open-mpi.org/community/lists/users/2016/03/28758.php > > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > _______________________________________________ > users mailing list > us...@open-mpi.org > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users > Link to this post: > http://www.open-mpi.org/community/lists/users/2016/03/28770.php
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