On Wed, 2011-05-25 at 19:06 -0400, Jeff Squyres wrote: > I'm not sure what you're saying here. There is a large difference > between "--mca a,b,c" and "--mca a,b". > > In the former, all 3 communication methods will be used (a, b, and c). > In the latter, only 2 will be used (a and b). > > To be clear, if you explicitly list which BTLs to use, OMPI will only > (try to) use exactly those and no others.
It might be worth putting the sm btl in the FAQ: http://www.open-mpi.org/faq/?category=openfabrics#ib-btl
