Finally, if you are talking about less than 100 interactive users it is likely that any relatively modern hardware can support it. If you are talking about having more than 1000 interactive users, you should know how to predict your utilization, go overboard on hardware, be willing to suffer growing pains, or be able to hire someone that can help.
There are a number of good performance tuning articles out for Solaris by Adrian Cockcroft. Go to your favorite search engine and look for his name.
A: If you're using Berkeley DB 3.0.55, try installing some patches to Berkeley DB available from http://www.sleepycat.com/update/3.0.55/patch.3.0.55.html.
A: Make sure /etc/sasldb is readable by the Cyrus user.
Jan 14 13:46:24 grant ctl_deliver[9060]: duplicate_prune: opening /var/imap/deliverdb/deliver-x.db: No such file or directory Jan 14 13:46:24 grant ctl_deliver[9060]: duplicate_prune: opening /var/imap/deliverdb/deliver-y.db: No such file or directory Jan 14 13:46:24 grant ctl_deliver[9060]: duplicate_prune: opening /var/imap/deliverdb/deliver-z.db: No such file or directoryin my cyrus.log file. What's wrong?
A: These messages are normal; one file is maintained for each user beginning with "x", "y", "z", etc. If you're first starting or you have no users beginning with these letters, these messages are completely normal and can be ignored.