[Dovecot] Too many imap connections in state "idling"
Hi,
I have a "Ubuntu12.04 + dovecot-2.0.19" configuration in my server. My mailbox server is shared by ~ 10k domains. It works fine with ~50k accounts.
On average, my server has about 6K simultaneous imap connections during office hours. But I've noticed that this server has an average of approximately 4k connections in state "idling".
On other Dovecot servers the average connections in state "idling" is only 10%.
My doveconf -n: http://thiagoh.prv.digirati.com.br/doveconf-n.txt
Can someone help me?
Thanks
Thiago Henrique adminlinux.com.br
Is it normal this large amount of connections in state 'idling' ?
Thanks
Thiago Henrique adminlinux.com.br
On 12-12-2012 11:52, 3.listas@adminlinux.com.br wrote:
Hi,
I have a "Ubuntu12.04 + dovecot-2.0.19" configuration in my server. My mailbox server is shared by ~ 10k domains. It works fine with ~50k accounts.
On average, my server has about 6K simultaneous imap connections during office hours. But I've noticed that this server has an average of approximately 4k connections in state "idling".
On other Dovecot servers the average connections in state "idling" is only 10%.
My doveconf -n: http://thiagoh.prv.digirati.com.br/doveconf-n.txt
Can someone help me?
Thanks
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
On Thu, 13 Dec 2012, 3.listas@adminlinux.com.br wrote:
Is it normal this large amount of connections in state 'idling' ?
If they actually using the "IDLE" command to wait for PUSH mails on much more folders than on the other server?
Regards,
Steffen Kaiser -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux)
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Thanks Steffen Kaiser ! I think not. The server is currently always 60% of imap processes in state "idling".
IDLE processes are like this: root@server:/root# ps aux |grep imap dovemail 617 0.0 0.0 23136 2260 ? S Dec15 0:01 dovecot/imap [Username1 IP1 IDLE] dovemail 677 0.0 0.0 23104 2172 ? S Dec15 0:01 dovecot/imap [Username2 IP2 IDLE] ...
My "idling" processes are seen as follows: root@server:~# ps aux |grep imap |grep idling dovemail 1141 0.0 0.0 16836 2148 ? D Dec15 0:01 dovecot/imap [idling] dovemail 3375 0.0 0.0 16828 2120 ? D 15:48 0:00 dovecot/imap [idling] dovemail 4833 0.0 0.0 16828 2212 ? D 15:49 0:00 dovecot/imap [idling] ...
Thanks!
Thiago Henrique www.adminlinux.com.br
On 14-12-2012 06:40, Steffen Kaiser wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
On Thu, 13 Dec 2012, 3.listas@adminlinux.com.br wrote:
Is it normal this large amount of connections in state 'idling' ?
If they actually using the "IDLE" command to wait for PUSH mails on much more folders than on the other server?
Regards,
- -- Steffen Kaiser -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux)
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On 18.12.2012, at 18.48, 3.listas@adminlinux.com.br listas@adminlinux.com.br wrote:
root@server:~# ps aux |grep imap |grep idling dovemail 1141 0.0 0.0 16836 2148 ? D Dec15 0:01 dovecot/imap [idling] dovemail 3375 0.0 0.0 16828 2120 ? D 15:48 0:00 dovecot/imap [idling] dovemail 4833 0.0 0.0 16828 2212 ? D 15:49 0:00 dovecot/imap [idling] …
"D" state means they're hanging in kernel. Can you look with gdb and strace what they're doing?
gdb -p 1141 bt full
strace -tt -p 1141
Can you see other strange symptoms on that machine? For example very high system load but not high I/O?
We had similar issues with imap processes that are hanging in "D" state some months ago. The problem was, or is a bug in the inotify mechanism in the linux kernel. Not shure if the bug has just been fixed.
For details see here: http://www.dovecot.org/list/dovecot/2012-May/065884.html
and solution here: http://www.dovecot.org/list/dovecot/2012-June/066314.html
Regards Urban
On 18.12.2012 17:48, 3.listas@adminlinux.com.br wrote:
Thanks Steffen Kaiser ! I think not. The server is currently always 60% of imap processes in state "idling".
IDLE processes are like this: root@server:/root# ps aux |grep imap dovemail 617 0.0 0.0 23136 2260 ? S Dec15 0:01 dovecot/imap [Username1 IP1 IDLE] dovemail 677 0.0 0.0 23104 2172 ? S Dec15 0:01 dovecot/imap [Username2 IP2 IDLE] ...
My "idling" processes are seen as follows: root@server:~# ps aux |grep imap |grep idling dovemail 1141 0.0 0.0 16836 2148 ? D Dec15 0:01 dovecot/imap [idling] dovemail 3375 0.0 0.0 16828 2120 ? D 15:48 0:00 dovecot/imap [idling] dovemail 4833 0.0 0.0 16828 2212 ? D 15:49 0:00 dovecot/imap [idling] ...
Thanks!
Thiago Henrique www.adminlinux.com.br
On 14-12-2012 06:40, Steffen Kaiser wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
On Thu, 13 Dec 2012, 3.listas@adminlinux.com.br wrote:
Is it normal this large amount of connections in state 'idling' ?
If they actually using the "IDLE" command to wait for PUSH mails on much more folders than on the other server?
Regards,
- -- Steffen Kaiser -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux)
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participants (4)
-
3.listas＠adminlinux.com.br
-
Steffen Kaiser
-
Timo Sirainen
-
Urban Loesch