[Dovecot] Lot of dovecot process writes
Hello,
While monitoring my servers' behaviour (ubuntu 12.04 with dovecot 2.1.9, with about 70000 users) I have found that lots of disk usage is done by dovecot process (the parent process). Since lmtp, imap and pop3 connections are handle by their own process, what could be the reason of this?
-- Angel L. Mateo Martínez Sección de Telemática Área de Tecnologías de la Información y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868889150 Fax: 868888337
Am 06.03.2013 13:15, schrieb Angel L. Mateo:
Hello,
While monitoring my servers' behaviour (ubuntu 12.04 with dovecot2.1.9, with about 70000 users) I have found that lots of disk usage is done by dovecot process (the parent process). Since lmtp, imap and pop3 connections are handle by their own process, what could be the reason of this?
maildir may no be optimal for such high amount of users, use i.e mdbox
http://wiki2.dovecot.org/MailboxFormat/dbox
Best Regards MfG Robert Schetterer
-- [*] sys4 AG
http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München
Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer Aufsichtsratsvorsitzender: Joerg Heidrich
El 06/03/13 13:22, Robert Schetterer escribió:
Am 06.03.2013 13:15, schrieb Angel L. Mateo:
Hello,
While monitoring my servers' behaviour (ubuntu 12.04 with dovecot2.1.9, with about 70000 users) I have found that lots of disk usage is done by dovecot process (the parent process). Since lmtp, imap and pop3 connections are handle by their own process, what could be the reason of this?
maildir may no be optimal for such high amount of users, use i.e mdbox
I know this. We are planning to migrate to dbox, but in a multiserver environment like ours is not so trivial because of indexes (we tried it with indexes in nfs storage but performance was poor).
In any case, I don't understand why dovecot parent process has these huge amount of IO, since, I guess, IO should be done by user's processes (lmtp, imap or pop), not dovecot parent.
My only hypothesis is related with log messages, but then IO should be done by rsyslog process, not dovecot, shouldn't it?
-- Angel L. Mateo Martínez Sección de Telemática Área de Tecnologías de la Información y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868889150 Fax: 868888337
Am 06.03.2013 13:44, schrieb Angel L. Mateo:
El 06/03/13 13:22, Robert Schetterer escribió:
Am 06.03.2013 13:15, schrieb Angel L. Mateo:
Hello,
While monitoring my servers' behaviour (ubuntu 12.04 with dovecot2.1.9, with about 70000 users) I have found that lots of disk usage is done by dovecot process (the parent process). Since lmtp, imap and pop3 connections are handle by their own process, what could be the reason of this?
maildir may no be optimal for such high amount of users, use i.e mdbox
I know this. We are planning to migrate to dbox, but in amultiserver environment like ours is not so trivial because of indexes (we tried it with indexes in nfs storage but performance was poor).
yes ,migrations on big systems, are always difficult
In any case, I don't understand why dovecot parent process has thesehuge amount of IO, since, I guess, IO should be done by user's processes (lmtp, imap or pop), not dovecot parent.
My only hypothesis is related with log messages,
but then IO should
be done by rsyslog process, not dovecot, shouldn't it?
dont think that this has impact, what about upgrading to recent version first, dont speculate, do real analysis
after all with such amount of users , you might want to use
Professional Services
i.e
http://www.dovecot.fi/services-and-solutions/
for optimizing your setup.
Best Regards MfG Robert Schetterer
-- [*] sys4 AG
http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München
Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer Aufsichtsratsvorsitzender: Joerg Heidrich
On 6.3.2013, at 14.44, Angel L. Mateo amateo@um.es wrote:
While monitoring my servers' behaviour (ubuntu 12.04 with dovecot2.1.9, with about 70000 users) I have found that lots of disk usage is done by dovecot process (the parent process). Since lmtp, imap and pop3 connections are handle by their own process, what could be the reason of this?
In any case, I don't understand why dovecot parent process has these huge amount of IO, since, I guess, IO should be done by user's processes (lmtp, imap or pop), not dovecot parent.
Right.
My only hypothesis is related with log messages, but then IO should be done by rsyslog process, not dovecot, shouldn't it?
Master process doesn't even log messages, log process does that.
There is no reason why dovecot master process would be doing any disk IO. Maybe whatever you're looking at is counting the child processes' disk IO as well?
participants (3)
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Angel L. Mateo
-
Robert Schetterer
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Timo Sirainen