Subject: Re: [vserver] vserver-stat: open(memory.usage_in_bytes): No such file or directory
From: "Daniel Hokka Zakrisson" <daniel@hozac.com>
Date: Wed, 27 Oct 2010 14:04:02 +0200 (CEST)

Gordan Bobic wrote:
> Daniel Hokka Zakrisson wrote:
>> Gordan Bobic wrote:
>>> Daniel Hokka Zakrisson wrote:
>>>> Gordan Bobic wrote:
>>>>> Art -kwaak- van Breemen wrote:
>>>>>> On Wed, Oct 27, 2010 at 09:57:44AM +0100, Gordan Bobic wrote:
>>>>>>> open(memory.usage_in_bytes): No such file or directory
>>>>>> Eh you should have a /dev/cgroup and /etc/init.d/util-vserver
>>>>>> should have mounted the cgroup fs.
>>>>>  >
>>>>>> Oh, and you should have support for containers in your kernel
>>>>>> ;-).
>>>>>> rlimits are replaced by container limits.
>>>>> I think I've found the cause. If the hostname in
>>>>> /etc/vserver/<guestname>/name isn't the same as <guestname>, this
>>>>> happens. I would suggest this is a bug because guest name and the
>>>>> hostname of the guest don't have to be the same. vserver-stat should be
>>>>> referring to guests by guest name not by the hostname in
>>>>> /etc/vserver/<guestname>/name.
>>>> What makes you think that?
>>> Because otherwise /etc/vserver/<guestname>/name file is redundant with
>>> <guestname> in the path and should thus not exist in the first place. If
>>> they have to be the same, one shouldn't be there at all.
>>
>> They don't have to be the same.  It also doesn't have anything to do with
>> your error.
>
> Yes it does. The cause of my error was that they were different.
> vserver-stat looked for files in /dev/cgroup/<guestname_name> where name
> is as specified by /etc/vserver/<guestname>/name. The list of guests to
> fetch the information is related to /etc/vserver/<guestname>.
>
> e.g.
>
> If there is:
> $ cat /etc/vserver/foo/name
> foo.bar
>
> vserver-stat will look for /etc/cgroup/foo for vserver foo, and this
> will fail because the relevant files are in /dev/cgroup/foo.bar/

Well, that's a bug. You can always override it with
/etc/vservers/<guest>/cgroup/name

> So it is a very real issue.
>
> Is this the case in the "stable" branch, too? ;)
>
> Gordan

-- 
Daniel Hokka Zakrisson