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Subject: Re: [OMPI users] very bad parallel scaling of vasp using openmpi
From: Joe Landman (landman_at_[hidden])
Date: 2009-08-18 15:08:47


Craig Plaisance wrote:
> The switch we are using (Dell Powerconnect 6248) has a switching fabric
> capacity of 184 Gb/s, which should be more than adequate for the 48
> ports. Is this the same as backplane bandwidth?

Yes. If you are getting the behavior you describe, you are not getting
all that bandwidth, or you are getting significant contention for
specific ports.

-- 
Joseph Landman, Ph.D
Founder and CEO
Scalable Informatics Inc.
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