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From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2007-10-25 10:55:25


On Oct 25, 2007, at 10:35 AM, Gleb Natapov wrote:

> I don't think xrc should be used by default even if HW supports it.
> Only if
> special config option is set xrc should be attempted.

Why?

> And xrc availability
> can be tested in runtime without additional options in ini file.

Is there a flag on the device / port that indicates XRC availability?

> I don't know iWarp enough to tell if it is possible to find out in
> runtime if rdma_cm is mandatory or other means of connection
> establishment can be used, but if there is no way to do it, then new
> parameter "hca_type" could be added to ini file with two possible
> values "ib" and "iwarp".

Yes, there is a flag on either the device or port (I forget which)
which indicates whether it's an iwarp or IB device. I think (at
least for today) we can assume that all iWARP devices require RDMA CM
-- right, iWARP guys?

So do you want the arbitration rules for which CPC to be used to be
hard-coded in the openib component (possibly overridden by MCA
parameter to force a specific selection)?

-- 
Jeff Squyres
Cisco Systems