On Mon, 2009-07-27 at 12:14 +0100, Guy wrote:

I've just tried upgrading from 1.1.8 to 1.2.2. As soon as the new version was started up the number of imap/pop3 processes began to climb to 800+, where I normally have about 300 or so connections at any given time. The load on the server also climbed to 150+.

I've reverted back to 1.1.18, which is running just fine, but is there anything I can do to help trace what was causing the problem? Unfortunately I don't have a clue where to start.

Besides the OS/Kernel version that Guillaume already asked, what did you see in Dovecot's logs? Any errors? Anything different in disconnect reasons? Also dovecot -n output could show something useful.