DoveCot vs Cyrus-Imapd Performance

[Aleksandar Milivojevic]

Quoting Kevin Fries <kevin at hcico.com>
Date: Fri, 14 Jan 2005 17:01:31

> You are trying to do 70,000 account on one server?  Are you f-ing nuts!!!!

Why not?  You have problems with that?

> That is what clusters are for!  Then, the standard directory structure
> of Dovecot becomes an even better idea.

Actually, we built Alpha cluster when numbers went above 100,000.  Mostly
becasue of redundancy.  As far as CPU power, the big Alpha server was doing just
fine.  If the big server smoked in the middle of the night, it would take us
hour or two to get spare running.  With cluster, there would be no downtime at all.

> This is just silly.  I would put Dovecot up even at a large
> university.  You are talking about AOL type numbers which is just
> craziness.

AOL/Yahoo/Hotmail/whatever type numbers would be something like 10m+ of active
accounts.

> I think I will start contributing to more sane conversations from here
> on out!
> 
> 100,000+ as normal, and on one server! lmao

100,000+ isn't an everyday, average mail server, but it isn't insane and
uncommon.  Small comapny will easilly have dozens of email accounts.  A bit
larger one will cope with 100+, maybe up to 1,000.  Go to government, schools,
universities, bigger companies, you move to 1,000-10,000 range.  ISPs differ in
what kind of customers they cover, and in size, but 10,000-100,000 range isn't
uncommon at all.  Big ones might need to cope with millions of mailboxes.

Also, it isn't only how many users there are.  100 users with hundreds of
megabytes or even gigabytes of email each in IMAP folders will easilly place
more load on the server, than 10,000 ISP mail users with 10 meg quota and POP3
only access over dial-up.

So yeah, single machine that manages 10,000 of student campus accounts with
liberal quota (disk is cheap), IMAP, and access over local campus ethernet,
might not be the smartest move.  10,000 typical dial-up POP3 users, that is
completely different story.

-- 
Aleksandar Milivojevic <amilivojevic at pbl.ca>    Pollard Banknote Limited
Systems Administrator                           1499 Buffalo Place
Tel: (204) 474-2323 ext 276                     Winnipeg, MB  R3T 1L7