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Subject: Re: [OMPI users] Factor of 10 loss in performance with 1.3.x
From: Steve Kargl (sgk_at_[hidden])
Date: 2009-04-07 14:31:10

On Tue, Apr 07, 2009 at 09:10:21AM -0700, Eugene Loh wrote:
> Steve Kargl wrote:
> >I can rebuild 1.2.9 and 1.3.1. Is there any particular configure
> >options that I should enable/disable?
> I hope someone else will chime in here, because I'm somewhat out of
> ideas. All I'm saying is that 10-usec latencies on sm with 1.3.0 or
> 1.3.1 are out of line with what other people see and I don't think it's
> simply a 1.2.9/1.3.0 issue here. I'm stumped.

With 1.3.2 pre-release, I ran

/usr/local/openmpi-1.3.2/bin/mpiexec --mca btl sm,self \
--mca mpi_show_mca_params all -machinefile mf_ompi_2 -n 2 ./z | & tee sgk.log

I've placed a file with the output from '--mca mpi_show_mca_params all' at

Perhaps, someone with more knowledge of the parameters can take a
quick look. I do observe

[] btl_sm_bandwidth=900 (default value)
[] btl_sm_latency=100 (default value)

Are these values tunable?