[Kolab-devel] Kolab troubles under high load

[Michael Harlaut]

Hi,

Matt Douhan a écrit :

>We are seing issues where FB generation will not work and synching IMAP 
>folders takes a looooong time, when the nr of emails > 5000 / hour.
>  
>
>I also tested the same onto a exim frontend server we use that also runs 
>amavaisd / clamscan, and it can handle the same load easily so I am wondering 
>if the kolab filter, may be the culprit here, is there a way to bypass the 
>kolab filter and still keep functionality? or at lest bypass for testing 
>purposes to see what is going on?
>  
>
I also made some tests with a postfix relay running amavisd / clamav / 
spamassassin on a PIV 2.5 Ghz with 2 Gb RAM.
It can handle ~ 7000 mails an hour (real mails to hundred of users, not 
by scripting) while being loaded primary by spamassassin.

I'm confident in postfix/cyrus/clam and even spamassassin, but I must 
admit I have some doubts concerning the kolab filter too, cause it seems 
to load the server more than all the others services in the same time 
(take care, perhaps I'm wrong)

Horde is also generating some load on the server, but it doesn't really 
have effects for us cause we use it only on a dedicated server (easier 
to manage, simplest to install and upgrade, and certainly more secure 
too). I have to admit I do not understand the choice of putting it on 
the same server than the "Kolab core" ...

We also use eaccelerator (http://eaccelerator.net/) for PHP caching, it 
helps a lot ! I also tested some IMAP proxys but the "boost" is not as 
impressive as with a PHP cache (and it needs some INGO hacks to make sur 
it does not connect on the IMAP proxy for SIEVE).

So ... for the moment, the only bottleneck I identified is also Kolab 
filter, but it certainly need more tests to be sure ...

I'm looking forward for other feedback !

Regards,

-- 
Michael HARLAUT

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