Performance problems, compared to wu-imapd

Tuomas Toropainen tjt at
Thu Jan 29 02:36:51 EST 2004

I have been running some performance tests on my cyrus test installation.  
The computer is not very fast, but my intention was just try how cyrus
performs compared to wu-imap on the same computer. It's 350Mhz P2 with
256MB memory and 4,5GB scsi disk. OS is redhat 9 and filesystem ext3. I'm
using mozilla mstone as benchmark program, and also when it has been
running, I have used squirrelmail to see how slow the imap service gets.
Mstone and squirrelmail are being run on other computers.

The problem is that wu-imapd seems to perform much better than cyrus.  
Cyrus version is 2.1.16, compiled with default database options. Syslog is
not logging debug messages, and has synchronous logging disabled (-). Both
systems have 500 test users, about 100 mails per user in INBOX. Mails are
generated with postal and are random text, max 20kB size. I also tried
with 100 users, the results are much same. Mstone results, squirrelmail
speed and computer load all tell that wu-imapd is faster.

For example, with 500 users, using cyrus mstone managed to retrieve 8,730
messages during 5 minute test, averaging 652.70ms per message. But using 
wu-imapd, 33,709 messages were retrieved, averaging 15.71ms per message.
Maximum concurrent connections was a little lower with wu-imapd (~180 vs 
220), but with cyrus computer load increased to 150 when there were 190 
imapd processes. Wu-imapd caused a maximum load of ~15.

What am I doing wrong, or is this computer just too slow for cyrus to 
perform well? Or are the default databases so poor that they cayse this?

Complete results are at (cyrus)
and (wu-imapd)

Thank you for any help :)

More information about the Info-cyrus mailing list