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Subject: [OMPI devel] latency and increasing number of processes
From: Terry Dontje (Terry.Dontje_at_[hidden])
Date: 2008-07-07 10:57:22

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?