[LAD] [Jack-Devel] JACK, cgroups and systemd

[Patrick Shirkey]

On Sun, January 12, 2014 11:17 pm, Dominique Michel wrote:
> Recently, I experimented with Debian sid, which use systemd. Systemd
> idea is nice, but its implementation is a catastrophe. It is more than
> one year I am using the kernel cgroups on gentoo to get rt scheduling
> with JACK, that without any trouble.
>
> On Debian, this is just impossible, because whatever I try, systemd
> insist to put what it think is good to have into the rt cgroup, which
> soon or later result in a complete system freeze with even dead magic
> keys. After loosing my time a few days with this, I removed Debian and
> installed gentoo instead.
>
> I found the reason here:
> http://article.gmane.org/gmane.linux.kernel/1063354
>
> "Lennart Poettering:
>
> Well, this feature is... completely irrelevant for normal desktop
> people.
> ...
> In fact, I just prepped a patch to systemd to move every service and
> every user session into its own cgroup in the 'cpu' hierarchy (in
> addition to the group it already creates in the 'systemd' hierarchy)."
>
> Another completely idiotic stuff of this guy.
>
> The point of the cgroups is it is possible to setup them for
> whatever use will be made with a computer, and this guy think he have
> the insane and pretentious capability to decide for every single user
> of the use they will made with their computers, and he is suggesting
> users doing something else are abnormal. He must be stopped!
>


That patch is over three years old. It seems like you have found a
loophole in the logic that was used to justify it.

Granted, it's annoying but it just means we have to find a better solution.

Similar to Fon's main objection to jack-session being *not flexible
enough*. We all knew it would cause problems for specific use cases but we
still haven't found a perfect solution to enable the flexibility that Fons
identified while also allowing people to get on with the task at hand.
Hence we have the less flexible but still useful for most use cases
version of jack session.



--
Patrick Shirkey
Boost Hardware Ltd