[imp] Slow mailbox list from time to time

[lst_hoe02 at kwsoft.de]

Zitat von Tornoci Laszlo <torlasz at xenia.sote.hu>:

> Hi,
>
> I have a Horde/IMP system that behaves strangely since I upgraded  
> from 3.1.5/4.1.5 to 3.3.4/4.3.4. I have about 400 users with 50-70  
> concurrent sessions usually. The IMAP mailstore (Cyrus) and the MTA  
> are on separate boxes. The system is dual Xeon (quad core) 2GHz, 2GB  
> RAM.
>
> We had excellent response times before the upgrade. The problem is,  
> we still have excellent response times (practically instantaneous  
> mailbox lists with > 3000 mails in one folder) most of the time, BUT  
> sometimes for long periods of time, I get miserable response times  
> (30-80 sec waiting) for the same large mailbox to be listed. "top"  
> show the http process to shoot up to 100% cpu while waiting, but  
> nothing else remarkable. Restarting http or mysqld doesn't help.  
> Logging in is not slow. The larger a mailbox, the worse the problem  
> is.
> After some time, response times get back to normal.

It *may* be Horde Alarms. As far as i remember there was a problem  
with the way Horde Alarms uses the Database in some configurations but  
i can't remember for sure. This could explain why you see it only  
occasionally. Another point to check is if you are using a PHP  
accelerator which do maintenance at the slow times.

Regards

Andreas