Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

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
system?

-stephen

-- 
Stephen Mulcahy, Applepie Solutions Ltd., Innovation in Business Center,
GMIT, Dublin Rd, Galway, Ireland.  +353.91.751262  http://www.aplpi.com
Registered in Ireland, no. 289353 (5 Woodlands Avenue, Renmore, Galway)