I've got some of our busiest users now using Dovecot instead of UW-IMAP with mbox-format mailboxes and predominantly Outlook Express as the client.
Doing some perfomance monitoring (with Solaris 8 process accounting), it looks like Dovecot needing to read only 30-50% of the disk blocks needed by UW-IMAP, but I was hoping for better!
What seems to happen, is that most of the connections use only a small number of blocks (due to Dovecot indexes, presumably) but occassionally a process will read lots of blocks, sometimes even more than a UW-IMAP session.
Is this expected, or is something going wrong with the index updates? I have the default sync settings, I think (mbox_dirty_syncs = yes, mbox_very_dirty_syncs = no, mbox_lazy_writes = yes)
My INBOX is an extreme example with ~10,000 messages and most processes reading a few hundred blocks but a couple using 20,000 or so!
Also, Dovecot seems to be dropping connections, sometimes, for no good reason (putting some extra i_info lines suggests for "inactivity"). Thunderbird tends to reconnect automatically, though. It seems it may be happening at the end of an IDLE command, something like:-
4 IDLE
- idling
- 1005 EXISTS DONE
- 1005 EXPUNGE
but then the expected
4 OK Idle completed
never comes.
Has anybody else seen this?
Best Wishes, Chris
-- --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+- Christopher Wakelin, c.d.wakelin@reading.ac.uk IT Services Centre, The University of Reading, Tel: +44 (0)118 378 8439 Whiteknights, Reading, RG6 2AF, UK Fax: +44 (0)118 975 3094