MetaSAN Slowdown after update

Greetings all, hope you're well and your SANs are running smoothly.

After upgrading recently to MetaSAN 2.2.2, I'm having some serious slowdowns when using the filesystem to access files (running OS X 10.4.10 on a G5). The bandwidth tests seem to be normal throughput-wise; but browsing files in the filesystem (Finder, open dialogs, etc.) as well as opening an FCP project from the SAN takes an abnormally long time - much, much longer than before updating. I tried to copy a 1.1 GB folder to the SAN, and it was reporting data rates of around 150K (!) per second - way below earlier performance.

Any idea why we'd see such a performance slowdown? I checked all the connections (which weren't disturbed during the update) and the fiber connections look normal. Video does seem to play ok, so far (which I find curious - why the file access slowdown but not throughput?).

Would the machines have started a Spotlight (mdimport) search after the update, for example? I didn't see any huge activity.

Any suggestions? Any other MetaSAN upgrade bugaboos?