[systemd-devel] systemd and cgroups

[Kay Sievers]

On Mon, Jan 13, 2014 at 5:35 PM, Thomas Bächler <thomas at archlinux.org> wrote:
> Am 13.01.2014 02:47, schrieb Kay Sievers:
>> On Mon, Jan 13, 2014 at 8:07 AM, Greg KH <gregkh at linuxfoundation.org> wrote:
>>> On Sun, Jan 12, 2014 at 11:48:56PM +0100, Dominique Michel wrote:
>>>> I need that pc for production, so I rapidly installed another
>>>> distribution without systemd. So this problem is solved for me, but
>>>> that doesn't solve that to force any user to use a default
>>>> configuration without any possibility of user setup, and without
>>>> documentation that can allow an user to do that, is just a design fault.
>>>
>>> That sounds like a distro issue, please take this up with your distro
>>> developers, this isn't a systemd issue.
>>
>> http://www.freedesktop.org/wiki/Software/systemd/MyServiceCantGetRealtime/
>
> Let me quote from that:
>
> "By default systemd places all system services into their own control
> groups in the "cpu" hierarchy."
>
> That is not true anymore since systemd 207 IIRC (whenever the whole
> cgroup rework started, I might have the version number wrong). In fact,
> systemd only puts services into the own cpu control group once you
> explicitly set the CPUShares for a service.
>
> "Instead of evening out CPU per process this will cause CPU to be evened
> out per service."
>
> This benefit has been lost with systemd 207, at least it is not the
> default behaviour anymore.

Yeah, that will all come back this year, when the new kernel cgroup
interfaces are ready.

The wiki should still apply to the above mentioned, a bit outdated,
version in Debian.

Kay