UC Davis Cyrus Incident September 2007

[Xue, Jack C]

Thanks for sharing your story. There are quite a number of large
Cyrus-IMAP installations around the world, especially in the
Higher-Education industry. 

We did a mass e-mail migration last year from OpenVMS to Cyrus/Postfix
on Linux 2.6. Comparing with UC-Davis, our systems have less activity as
our Faculty/Staff are using MS Exchange. 40K student users were split to
2 backends. We further divided these users to four 7-disc RAID5 sets
(10K users each) on an EMC SAN. Cyrus BDB directories use separate
mirror sets (also on the SAN). 

Based on your description, there is a bottleneck of how many concurrent
processes a backend can handle. Although this might be Solaris-related,
I am very interested in the ongoing investigation into this issue. I
believe that Cyrus Replication setup can perform better for high volume
sites. 

Jack C. Xue