Network adapter.

Felix Rauch rauch at inf.ethz.ch
Wed Nov 8 07:36:31 PST 2000


On Wed, 8 Nov 2000, Jon Tegner wrote:
> I have done some further testing, using netpipe
> (http://www.scl.ameslab.gov/Projects/ClusterCookbook/nprun.html). That
> application sends packages of increasing size between two nodes, and
> there is a drastic reduction in throughput when the size of the block
> approaches around 5800 bytes. For 5780 bytes speed is 67.45 Mbps and
> for 5800 bytes it is 1.34 Mbps. For increasing sizes it stays low (at
> least up till 1e6 bytes (where I stopped)).

I didn't follow this discussion closely, but this sounds like a
problem with the duplex-configuration. Make sure that your cards and
your switch have the same setting: Either everyone has full-duplex or
everyone has half-duplex (full-duplex is better).

- Felix
-- 
Felix Rauch                      | Email: rauch at inf.ethz.ch
Institute for Computer Systems   | Homepage: http://www.cs.inf.ethz.ch/~rauch/
ETH Zentrum / RZ H18             | Phone: ++41 1 632 7489
CH - 8092 Zuerich / Switzerland  | Fax:   ++41 1 632 1307





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