[Lxc-users] lxc-destroy does not destroy cgroup

[Gordon Henderson]

On Sun, 11 Dec 2011, Arie Skliarouk wrote:

>>
>> When I tried to restart the vserver, it did not came up. Long story short,
>> I found that lxc-destroy did not destroy the cgroup of the same name as the
>> server. The cgroup remains visible in the /sys/fs/cgroup/cpu/master
>> directory. The tasks file is empty though.
>>
>> I had to rename the container to be able to start it.
>>
>
> About 18 hours after the event, the physical machine locked up hard.
> Without any message in dmesg or on its console. Before that, the machine
> worked pretty hard for about 60 days without a hitch.

Ouch. And oddly enough, I had a hard-lockup a few days ago myself that 
needed a power cycle.

> My gut feeling is that it is related to the stale cgroup somehow.
>
> Out of curiosity, what kernel are you running? I'm on 2.6.35, but looking
>> at some of the later ones now...
>
> I use kernel 3.0.0-12-server amd64 as packaged in the ubuntu 11.10. I had
> problems with earlier kernels as they locked up the machine every week or
> so.

My base is Debian Stable, but I custom compile the kernels to match 
hardware. I've put the latest & greatest on a test server to see how it 
fares - so-far so good, but there's no real load on it.

I think it would be good for more people to start to post their 
experiences with LXC though - who knows how many people are using it - any 
"big" companies using it in anger (as opposed to KVM, XEN, etc.) and so 
on. (or small companies with big installations!)

I have 2 areas of application for it - one is hosted Asterisk PBXs, and 
for that it seems to work really well, but the run-time environment is 
very carefully controlled - it basically runs sendmail, sshd, apache+php 
and asterisk and nothing else. The other application I use them for it 
more of a management side - for running general purpose LAMP servers in - 
mostly to make sure I can relatively quickly move an image from one server 
to another to cover hardware issues or temporarily/permanent increase (or 
reduction!) in avalable resources... I don't consider my own use "big" by 
any means at all though..

Gordon