[Dovecot] Ongoing performance issues with 2.0.x

[Ralf Hildebrandt]

* Timo Sirainen <tss at iki.fi>:
> On 5.11.2010, at 9.58, Ralf Hildebrandt wrote:
> 
> > I uploaded a preliminary screenshot with comments:
> > http://www.arschkrebs.de/bugs/dovecot.png
> 
> Were you using v1.2's deliver here in left also? Or how much of a difference did that make alone?

2.0 was indeed using v1.2's deliver, and that made SOME difference
(less load)

Now with 1.2 I'm of course using v1.2's deliver

> How many imap logins per minute (or something) do you get? 
imap: about 70 / minute
imaps: about 50 / minute
pop3: none
pop3s: about 10 / minute 

these are all peak values during noon!

> What about pop3? Are you using a webmail that opens lots of short
> connections (and are people using webmail much)?

webmail (Squirrelmail) is using imapproxy.
 
> I'm wondering if the problem has to do with the way processes now do
> IPC 

That could very well be. Lots of time is spent in the kernel

> or is there just some bug(s) in the mail handling code..


-- 
Ralf Hildebrandt
  Geschäftsbereich IT | Abteilung Netzwerk
  Charité - Universitätsmedizin Berlin
  Campus Benjamin Franklin
  Hindenburgdamm 30 | D-12203 Berlin
  Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962
  ralf.hildebrandt at charite.de | http://www.charite.de