Hello,
I have been running Courier-IMAP for while now, and I decided that I'd like to try Dovecot. This paper: http://student.iu.hio.no/~s132278/reports/disney_imap_maildir.pdf says that the performances are somewhat comparable, but my Dovecot "feels" slower than Courier-IMAP.
I am using Maildirs and I have substantial amounts of emails in them. For example one of the folder has 26000 messages and to display a message it takes 6-7 seconds. Before it took only 2-3 seconds to display a message (in Thunderbird).
I have tried to turn "fsync_disable" to yes, but the feeling is somewhat the same. What else can I try to tune? It's a FreeBSD 6.2 machine on a HP ProLiant ML350 with 2GB RAM and 120GB SATA disk and the Dovecot running in a FreeBSD jail.
You can find my dovecot.conf here: http://pastebin.ca/627442
Thanks, Nejc