I've just upgraded our production zimbra server to 6.0.6 from 5.0.16. The upgrade went successfully, nothing untoward happened and the server started back up nicely.
Its sending and receiving mails as normal, and IMAP/POP access seems fine.
The problem is the web interface. It now seems to be taking a very long time to log in, and once logged in, certain activities such as viewing the calendars seem to take a long time to appear. The calander will open and show as blank, but after a minute or two the data will appear.
It seems, at least in part, related in some way to how full the users account is, my admin account for instance has no mail in it, and loads instantly.
The server itself doesnt appear to be under any sort of major load when this occurs, perhaps 5-10% cpu but nothing more. Theres over a GB of RAM free too.
I've had a look thru some of the log files and cant see anything of note, so i'd really like some pointers where to look next?