I'm one of the admins of a largish Qmail installation (~60,000 mailboxes)
and the hardware we're running it on it near the limit.
(Sun Ultra 450, dual processor, A1000 storage array)
The system is very IO bound, sometimes with a load average of 20-25.
(although usually between 3-8)
Now, we called Sun, asking about a high capacity disk solution, one that might
help with the IO problems. (cache on the disk array to take care of all the
fsyncs Qmail does)
They told us that around 50k-60k mailboxes is about the limit of Qmail.
Now, my question to all of you is how expandable is Qmail, and what's the best
way to do it?
We're looking to expand the system to 150,000-200,000 mailboxes.
How does Qmail deal with a single storage array linked to multiple load
balenced servers?
Greg
