[vPostMaster] weird load issue

[Scott Kleihege]

On Fri, Mar 14, 2008 at 12:31:58PM -0600, Wallace Winfrey wrote:
> The load on our (dual 3GHz) machine has been stuck at 70+ for the last hour 
> or so. I'm running htop and sorting by CPU process, and all the processes 
> are showing 0% CPU usage. We are, however, swapping like crazy, and there 
> seem to be around 100 vpostmaster-owned imap processes, some going back as 
> far March 12th, but a big number of them are an hour or two old.
>
> We've been used to our load being really high (our monthly average is 4.25) 
> but for the last few days, it's been insane, the average has been 10. I'm 
> about to reboot the machine (hopefully that will fix it) but it would be 
> nice if we could figure out what's going on here. I had been thinking that 
> spamd/clamav was the culprit, and while I know they put a significant load 
> on the machine, now I'm not so sure.

I believe there are problems with certain versions of clamav that cause
it to consume an excessive amount of CPU time under some circumstances.  I
ran into that problem last month and changing clamav versions caused clamav 
processing to speed up by about 1000 times.

It might be worth trying a newer version of the clamav packages.

If you're using CentOS or Red Hat Enterprise Linux, I'd suggest the Extra
Packages for Enterprise Linux repository.

   http://fedoraproject.org/wiki/EPEL

It has a few extra dependencies on several fedora-usermgmt packages, so I
would use yum to install the packages.

-- 
Regards,                    tummy.com, ltd
Scott Kleihege              Linux Consulting since 1995
                            http://www.tummy.com/