Cisco switches for lam mpi

Jack Douglas jd89313 at
Tue Jul 29 12:37:37 EDT 2003


I wonder if someone can help me

We have just installed a 32 Node Dual Xeon Cluster, with a Cisco Cataslyst 
4003 Chassis with 48 1000Base-t ports.

We are running LAM MPI over gigabit, but we seem to be experiencing 
bottlenecks within the switch

Typically, using the cisco, we only see CPU utilisation of around 30-40%

Howver, we experimented with a Foundry Switch, and were seeing cpu 
utilisation on the same job of around 80 - 90%.

We know that there are commands to "open" the cisco, but the ones we have 
been advised dont seem to do the trick.

Was the cisco a bad idea? If so can someone recommend a good Gigabit switch 
for MPI?  I have heard HP Procurves are supposed to be pretty good.

Or does anyone know any other commands that will open the Cisco switch 
further getting the performance up

Best Regards


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