nfsd spikes when remote mount
We are installing Fedora 16 on our office workstations (up from F12). We are not using NFSv4 (although I can't seem to make the nfsd4 process go away). We export filesystems in the usual way with /etc/exports, but when an older system (an F12, Slackware, RHEL) mounts this filesystem and tries to do anything with the files there, the number of nfsd process on the server (the F16 system) doubles or triples and the CPU usages spike to as high as 50% per process. This renders the mount unusable, and the server itself unusable.
The only workaround that I can find is to specify udp for the protocol when mounting. Any idea why this is? It's not a good workaround. If I must do something like this, I'd prefer to set something on the server rather that on 100 potential clients.
Any insight would be appreciated.