On Wed, 2007-05-09 at 08:37 +0300, Or Gerlitz wrote: > Andrew Friedley wrote: > > Jeff Squyres wrote: > >>>> FWIW, yes, adding RDMA CM support has actually been on my to-do list > >>>> for a while, but it keeps getting bumped by higher priority items. > >>>> It would be *much* better if some iWARP companies got involved in > >>>> Open MPI... > > > Hmm I'm interested. I've already done some work switching over to RDMA > > CM for some research stuff I've been doing; it's not publicly accessible > > w/o the 3rd party agreement. I can help answer questions on what > > exactly needs to change, and do some testing. > > Doing a bit of zoom out from the "how to make ofed's udapl work for > ompi" thread, my thinking is that the ompi udapl btl enablement is > actually only the first step, where for production/longterm/etc you want > to have an rdmacm btl. Reasoning here is made of many arguments, among > them the quickest i can make are: > > A) it seems that ompi would want to use not only RC but rather also UD > multicast and unicast, which are not covered by udapl > > B) there's actually no real justification to maintain two APIs (namely > udapl vs libibvers/librdmacm), so down the road, only one of them would > survive (udapl is implemented ***over*** libibverbs/librdmacm so if the > latteres dies same does udapl). Specifically, I hear here and there that > the OFED stack is now on its way to be deployed all over the place, > specifically in commercial Unix OSs (which want modern! code that > supports IPoIB-CM,RDS,SRP,iSER, etc you named it) so eventually the > rdmacm btl can be used also over Solaris et al. >
Agreed. enabling udapl will get OMPI over iwarp immediately (and hopefully in ofed-1.2). Post ofed-1.2, I think OMPI _should_ create a rdma-cm btl. That's the plan... Steve.
