cgroup: status-quo and userland efforts

[Serge Hallyn]

Quoting Andy Lutomirski (luto at amacapital.net):
> On 06/27/2013 11:01 AM, Tejun Heo wrote:
> > AFAICS, having a userland agent which has overall knowledge of the
> > hierarchy and enforcesf structure and limiations is a requirement to
> > make cgroup generally useable and useful.  For systemd based systems,
> > systemd serving that role isn't too crazy.  It's sure gonna have
> > teeting issues at the beginning but it has all the necessary
> > information to manage workloads on the system.
> > 
> > A valid issue is interoperability between systemd and non-systemd
> > systems.  I don't have an immediately good answer for that.  I wrote
> > in another reply but making cgroup generally available is a pretty new
> > effort and we're still in the process of figuring out what the right
> > constructs and abstractions are.  Hopefully, we'll be able to reach a
> > common set of abstractions to base things on top in itme.
> > 
> 
> The systemd stuff will break my code, too (although the single hierarchy
> by itself won't, I think).  I think that the kernel should make whatever
> simple changes are needed so that systemd can function without using
> cgroups at all.  That way users of a different cgroup scheme can turn
> off systemd's.
> 
> Here was my proposal, which hasn't gotten a clear reply:
> 
> http://article.gmane.org/gmane.comp.sysutils.systemd.devel/11424

Neat.  I like that proposal.

> I've already sent a patch to make /proc/<pid>/task/<tid>/children
> available regardless of configuration.

-serge