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Subject: Re: [OMPI devel] latency and increasing number of processes
From: Brian W. Barrett (brbarret_at_[hidden])
Date: 2008-07-07 11:00:04


On Mon, 7 Jul 2008, Terry Dontje wrote:

> Just curious has anyone done comparisons of latency measurements as one
> changes the size of a job. That is changing the size of the job (and number
> of nodes used) and just taking the half roundtrip latency of two of the
> processes in the job. I am roughly seeing an addition of 5% to the latency
> for each node added. This is with the TCP and Udapl BTLs. I am curious
> whether other BTLs have similar issues and if doing some sort of directed
> polling would help matters?

Is this on Solaris, Linux, or both?

Brian