lkml.org 
[lkml]   [2018]   [Aug]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH RFC 1/3] cgroup: list all subsystem states in debugfs files
On Mon, Aug 13, 2018 at 06:48:42AM -0700, Tejun Heo wrote:
> Hello, Konstantin.
>
> On Mon, Aug 13, 2018 at 09:58:05AM +0300, Konstantin Khlebnikov wrote:
> > After removing cgroup subsystem state could leak or live in background
> > forever because it is pinned by some reference. For example memory cgroup
> > could be pinned by pages in cache or tmpfs.
> >
> > This patch adds common debugfs interface for listing basic state for each
> > controller. Controller could define callback for dumping own attributes.
> >
> > In file /sys/kernel/debug/cgroup/<controller> each line shows state in
> > format: <common_attr>=<value>... [-- <controller_attr>=<value>... ]
>
> Seems pretty useful to me. Roman, Johannes, what do you guys think?

Generally I like the idea of having more introspection into offlined
cgroups, but I wonder if having only memory= and swap= could be a
little too terse to track down what exactly is pinning the groups.

Roman has more experience debugging these pileups, but it seems to me
that unless we add a breakdown off memory, and maybe make slabinfo
available for these groups, that in practice this might not provide
that much more insight than per-cgroup stat counters of dead children.

\
 
 \ /
  Last update: 2018-08-13 19:11    [W:0.155 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site