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From: stephen mulcahy (smulcahy_at_[hidden])
Date: 2007-04-19 08:15:40

Jeff Squyres wrote:
> That's truly odd -- I can't imagine why you wouldn't get the TCP
> transport with the above command line. But the latencies, as you
> mentioned, are far too low for TCP.
> To be absolutely certain that you're not getting the IB transport, go
> to the $prefix/lib/openmpi directory and make a bogus subdirectory
> (e.g., "mkdir foo"). Then move the *openib* and *mvapi* components
> into that subdirectory (you'll likely only have either "openib" *or*
> "mvapi" -- not both).
> Then try running again.

What is stranger still is that I can't find any *openib* or *mvapi*
components in that subdirectory so I'm left wondering what exactly it's
using to communicate. I don't think it's using shared memory because
I've run a shared memory test aswell and the latencies are lower with that.

Perhaps it's interacting with something else installed somewhere on the


Stephen Mulcahy, Applepie Solutions Ltd., Innovation in Business Center,
GMIT, Dublin Rd, Galway, Ireland.  +353.91.751262
Registered in Ireland, no. 289353 (5 Woodlands Avenue, Renmore, Galway)