[Dovecot] IMAP-proxy or not with sogo webmail and dovecot backend

[Jan-Frode Myklebust]

On Mon, Feb 13, 2012 at 04:14:22PM +0200, Timo Sirainen wrote:
> > The responstimes are not very fast, but they do seem to support
> > the claim that an imapproxy isn't needed for dovecot.
> 
> That's what I always suspected, but good to have someone actually test it. :) This is with Maildir?

Yes, this is maildirs (on GPFS).

> 
> Other things that would be interesting to try out (both from latency and disk IO usage point of view):
> 
>  - maildir_very_dirty_syncs

We already have

	$ doveconf maildir_very_dirty_syncs
	maildir_very_dirty_syncs = yes

but I don't think this gave the advantage I was expecting.. Was
expecting this to move most iops to the index-luns, but the maildir
luns seems just as busy.

>  - mail_prefetch_count (Linux+maildir only, v2.1+)

Will look into if this works with GPFS when we upgrade to v2.1. It has
it's own page cache, so I have no idea if it will respect
POSIX_FADV_WILLNEED or if one will need to use it's own API's for
hinting:

	http://publib.boulder.ibm.com/infocenter/clresctr/vxrx/index.jsp?topic=%2Fcom.ibm.cluster.gpfs.v3r4.gpfs300.doc%2Fbl1adm_mlacrge.html


  -jf