News to me. If the database is too busy, you should get a timeout screen or a "cannot contact database server" error message.
We don't know exactly why this problem happens, but it's probably caused by loss or temporary unavailability of session data. Brion says we still got these reports when we put sessions in NFS, so memcached can't explain the problem in its entirety, but nonetheless I'd be inclined to think the current increase in reports is due to load on the memcached servers. We should probably try installing memcached on another 10 or 15 servers and see if that fixes the problem.
A closely related problem is being spontaneously logged out if you didn't select the "remember me" checkbox when you logged in.
-- Tim Starling
I've noticed that problem since the upgrade - sometimes a second or third submit does it, sometimes it never works and I just copy the edit to notepad, close Firefox, and try again. I'd say it happens maybe every third edit. This is very different from the timeout messages.
Ian (Guettarda)