Bug#777601: systemd: Loosing LXC memory cgroups after service install

[Pierre Mavro]

Hi Martin,

So many questions...thanks for answers !

I think this may not be a critical bug, however as this is the only way
(as far as I know) to know/monitor the used resources of a container, I
think it's important. Not just a cosmetical problem.

To my level, it's hard to say if this issue is linked or not
(https://bugzilla.redhat.com/show_bug.cgi?id=1139223). But, what I can
see is, swap and memory are both options that requires to be activated
from grub to work compared to others which work out of the box.

This issue really looks like the same
(http://lists.freedesktop.org/archives/systemd-devel/2014-September/023276.html).
It may be a good idea to integrate this patch.

I also tested something which may be another problem (so another ticket)
but the memory and swap limitation doesn't work at all :-(...with or
without this bug. I can't tell if it's linked or not.
I tested cpu pinning and it works like a charm. The issue seems related
to memory and swap only.

Thanks

Pierre

Le 02/12/2015 03:43 PM, Martin Pitt a écrit :
> Control: tag -1 pending
>
> Hello again,
>
> so the patch that got proposed at
>
>   http://lists.freedesktop.org/archives/systemd-devel/2014-September/023276.html
>
> actually makes a lot of sense: This makes systemd only clean up
> cgroups that it created by itself, and thus won't clean up empty ones
> in other controllers that LXC created. I tested this and committed
> this for the experimental branch for now:
>
>   http://anonscm.debian.org/cgit/pkg-systemd/systemd.git/commit/?h=experimental&id=286ef78fd
>
> I'd like to see this out in the wild for some time before applying it
> to jessie, though. I'm also still interested in what the actual impact
> of that is -- critical seems rather inflated? Losing empty cgroups
> doesn't sound that dangerous after all, aside from the LXC warnings
> when shutting down a container?
>
> Thanks,
>
> Martin