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!