Hi,
I am running a fair amount of stored e-mails on maildirs(10 GB+) in 846 folders that gets a fair amount of searching, and 20+ users accessing them, mostly via IMAP and a few POP3 accounts. I am running these on a Linode XEN server and have yet to hit any hard limits of "bare metal". User and Virual databases are plain text files.
# 1.2.9: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32.16-linode28 i686 Ubuntu 10.04.1 LTS ext3
Postfix + Dovecot + SSL for Both with Amavisd seems a breeze. No problems related to infrastructure yet.
Yet I will wait to see how this system will grow, as we are planning to include more users and doamins in our system in 2011.
So:
- I am very interested in these questions about performance
- My setup should provide some people another way to do things, since I am not using mysql, ldap etc., kust plain old text files update via scripts
- I am goind to test this system as we scale out, yet we are bound to add LDAP for authentication for single sign on at some point, and I will try to publish my benchmarks public, even if it is just for publicity's sake.
Regards, Kerem
On Sat, Dec 11, 2010 at 6:47 PM, Eric Rostetter rostetter@mail.utexas.eduwrote:
Quoting a@test123.ru:
Guys. Who is interested in obvious reasoning?
The same people who are interested in vague questions?
Let me remind original concrete question. I am also interested.
We can "exchange" CPU & RAM to minimize disk i/o.
Should we change to dovecot 2.0? Maybe mdbox can help us? Maybe ext4 instead of ext3?
Uhm, well, again, depends on your needs. Pop3? Imap? Both? Number of accounts? Can't really help without more details. Maybe I can't help with more details either, but that is a risk you take on a mailing list.
- Is migration to dovecot 2.0 good idea if I want to decrease I/O?
Depends on what version you run now really. But I would recommend it anyway just on principle.
- Can mdbox help decrease IO?
- What is better for mdbox or maildir - ext3 or ext4?
Dont' know. But you can certainly tune the FS in either case (atime/dtime, flush rate, external journal, etc). Some will say XFS is better, etc. Besides, you can hardly decide the best FS until you know the mailbox format (mbox, maildir, mdbox, etc).
If you want concret answers, you need concret questions...
-- Eric Rostetter The Department of Physics The University of Texas at Austin
Go Longhorns!
-- Kerem Erciyes Sistem Danismani http://proje.keremerciyes.com
kerem.erciyes@gmail.com +90 532 737 05 83