[Beowulf] recommendations for a good ethernet switch for connecting ~300 compute nodes

[Mark Hahn]

> allows global cross mounts from ~300 compute nodes) There is a variety
> of codes we run; some latency sensitive and others bandwidth
> sensitive.

if you're sensitive either way, you're going to be unhappy with Gb.
IMO, you'd be best to configure your scheduler to never spread an MPI
job across switches, and then just match the backbone to the aggregate 
IO bandwidth your NFS storage can support.

something like 10G uplinks from 48pt switches would probably work well.