[Dovecot] Very High Load on Dovecot 2 and Errors in mail.err.

[Urban Loesch]

Hi,

yesterday I disabled the inotify as mentioned in the previous post
and it works for me also. Thanks to all for the hint.

On 20.06.2012 08:35, Jesper Dahl Nyerup wrote:
> On Jun 11  23:37, Jesper Dahl Nyerup wrote:
>> We're still chasing the root cause in the kernel or the VServer patch
>> set. We'll of course make sure to post our findings here, and I'd very
>> much appreciate to hear about other people's progress.
>
> We still haven't found a solution, but here's what we've got thus far:
>
>   - The issue is not VServer specific. We're able to reproduce it on
>     recent vanilla kernels.
>
>   - The issue has a strong correlation with the number of processor cores
>     in the machine. The behavior is impossible to provoke on a dual core
>     workstation, but is very widespread on 16 or 24 core machines.

For the records:
I have the problem on 2 different machines with different CPU's
- PE2950 with 2x Intel Xeon X5450 3.00Ghz (8) CPU's (problem happens not so often as with PER610)
- PER610 with 2x Intel Xeon X5650 2.67GHz (24) CPU's

>
> One of my colleagues has written a snippet of code that reproduces and
> exposes the problem, and we've sent this to the Inotify maintainers and
> the kernel mailing list, hoping that someone more familiar with the code
> will be quicker to figure out what is broken.
>
> If anyone's interested - either in following the issue or the code
> snippet that reproduces it - here's the post:
> http://thread.gmane.org/gmane.linux.kernel/1315430

As you described on the kernel maillinglist, I can confirm. The higher the
number of cpu's, the worse it gets.

>
> As this is clearly a kernel issue, we're going to try to keep the
> discussion there, and I'll probably not follow up here, until the issue
> has been resolved.
>
> Jesper.

Thanks
Urban