nfs scalability?

[lazyevil at yahoo.com]

Hey y'all,

So.. I'm running a Redhat system w/ a fibre connected DAS pushing out 
NFS to > 40 client machines right now.. and we're starting to feel the 
performance hits.  I know you've handled this before.. here's what I've 
looked at/thought of, I'd love to hear some more ideas..

- nfs tuning: i've been using http://www.iozone.org to tweak
    - nfsd thread count, rmem/wmem sizes, rsize/wsize, etc..
- replacing nfs server w/ better hw
- adding second nfs server connected to DAS, splitting mount points
- switching to TCP - anyone tried this out yet?  on RH-WS3?

I'm tired of writing cron jobs to fix the automounter, and deal with 
stale file handles.. its time to upgrade or find something else..

Ciao,

-steve