[Dovecot] mail spool filesystem

[Thomas Harold]

On 8/17/2011 9:23 AM, Julio Cesar Covolato wrote:
> Hi!
>
> I´m about to migrate a system whith 5000 accounts whith (~ 500GB) from
> "postfix/courier-imap/maildrop/mysql" to a new hardware whith
> "postfix/dovecot/dovecot/mysql".
>
> I´ll make a separate partition (raid 1) for the mail spool
> (/var/spool/vmail) and want to now what type of filesystem to use on it
> to increase performance. I read that XFS is a good choice, but is not
> too reliable...

We run ext3 and ext4.  Individual mailboxes with a few hundred thousand 
messages in Maildir on top of ext3 ran fine (800k messages, 4GB mailbox 
was not unusual).  Slowly migrating file systems over to ext4 as we have 
time (or rollout new hardware).

Frankly, for that big of a mail store, I'd go with RAID 1+0 over a 
minimum of 4 spindles for the storage of the mbox / Maildir files.  If 
you have heavy usage, seek time might be your biggest enemy.

Keeping the postfix spools (/var/spool/postfix) on a separate set of 
disks (like the RAID 1 array that you use to run the operating system 
off of) helps.