Poor NFS Performance (when all users active?)

dmarshx wrote:
SNMP access to the CPU and MEMORY counters show plenty of free RAM and low CPU Usage.

That may well be for the task may still be "busy" with looking up inodes on the file system.

dmarshx wrote:
In your environment what constitutes "too many files"? I've seen 32K listed as a limit, but never any number less than that.

I *try* to have our developers build applications in such a way as to never create more than ~2048 files per directory. Actually, the inner workings behind the scenes are a lot more complex than that. In reality, on an EXTx filesystem, you define the number of inodes and with that the number of expected dir entries on creation of the file system. The system then creates "space" for the estimated amount of files/dirs for faster indexing. If you cross the initial limits, creation of files and dirs is still possible, but instead of the reserved blocks secondary areas of the hard-disk will be used. The net effect is that after a certain point, additional and thus "costly" seeking of the hard drive's heads occurs. Especially in multiuser environments this can get problematic pretty fast. So my current guess is that your NFS acts the way it does because you crossed a boundary on the ReadyNAS' local filesystem. But of course that's just a guess.

-Stefan