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Subject: Re: [OMPI users] TCP Bandwidth
From: Andy Georgi (Andy.Georgi_at_[hidden])
Date: 2008-08-18 04:00:24

Steve Wise wrote:
> Are you using Chelsio's TOE drivers? Or just a driver from the distro?

We use the Chelsio TOE drivers.

Steve Wise wrote:
> Ok. Did you run their script?

Yes, if not we wouldn't get the 1.15 GB/s on the TCP level. We had ~800 MB/s before
primarily because of too small TCP buffers.

The difference of more than 200 MB/s between 1.15 GB/s we get with iperf and the 930 MB/s we
measured with a MPI-Ping-Pong test is too large, i think. Something in Open MPI seems to slow it down.

Dresden University of Technology
Center for Information Services
and High Performance Computing (ZIH)
D-01062 Dresden
e-mail: Andy.Georgi_at_[hidden]