DoveCot vs Cyrus-Imapd Performance

[Craig White]

On Fri, 2005-01-14 at 17:01 -0700, Kevin Fries wrote:
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> Aleksandar Milivojevic wrote:
> 
> | 700 users is nothing.  You will not see any problems with
> | scalability with that user base.  Multiply it by 100, and you'll
> | start seening first problems.  Go past 100,000, and things get
> | preaty tight.
> |
> | Before my wife talked me into moving to Canada (and out of all the
> | warm places in Canada, Winnipeg was our destination), I've used to
> | work for large national ISP where user's were stored in actual
> | /etc/passwd.  Mail server worked well until user base got to about
> | 50,000 users on 4-CPU Alpha Server running Tru64 Unix (and later
> | cluster of several Alpha Servers).  Then, Internet boom hapened, and
> | user base exploded.  Things started to slow down drastically with
> | each new user.  Local system accounts proved not to be very scalable
> | solution.  In those days, there were no out-of-box solutions based
> | on LDAP, like there are today.  So what we did back than, we moved
> | all users from shell accounts into Oracle database, and made patches
> | for sendmail, procmail, and qpopper to work with users that exist
> | only as records inside Oracle SQL database. That same 4-CPU Alpha
> | Server that was beginning to be painfully slow, all the sudden was
> | capable of hosting several milion mailboxes.  Now, that is what I
> | have in mind when I say scalability.
> |
> | If we were to do it again today, we'd probably simply use LDAP and
> | Cyrus, with little development time spent for transition.
> |
> You are trying to do 70,000 account on one server?  Are you f-ing nuts!!!!
> 
> That is what clusters are for!  Then, the standard directory structure
> of Dovecot becomes an even better idea.
> 
> This conversation has just gotten stupid, one server for 70,000
> account, you just are not dealing with a normal situation.  The
> majority of companies (greater than 70%) are less than 100 people
> large.  The majority of corporations will never get that large because
> they will use a server in front to direct the mail to the remote
> offices local mail server where 5k-10k is considered huge.  To follow
> your logic we should all have NASA space shuttles because a small
> percentage of us go into space.
> 
> 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.
> 
> I think I will start contributing to more sane conversations from here
> on out!
> 
> 100,000+ as normal, and on one server! lmao
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1 - he actually said they had an Alpha cluster for that job
2 - his point was about primarily scalability
3 - I have never used either Dovecot or Cyrus and don't have a dog in
this hunt. But I can never ignore the amount of resources an imap server
expends servicing clients and efficiency can be key - whether it is 50 -
100 or 100,000 clients. It is almost certain that the clients that I
work with (10-30 employees) - this server is doing more than just imapd.
4 - Cyrus genetics are good in that it is used by large mail systems.
5 - Cyrus support quota's separately from OS
6 - Webmin LDAP Users and Groups is integrated with Cyrus

Dovecot may be great but Cyrus-imapd has a bunch going for it.

Craig