<http://www.horde.org/horde/docs/?f=PERFORMANCE.html> Under "IMAP tuning" the link for Cyrus is <http://asg.web.cmu.edu/cyrus/download/imapd/install-perf.html> which is out of date. The correct link [currently] should be <http://www.cyrusimap.org/docs/cyrus-imapd/2.4.2/install-perf.php>