diff options
| author |   Boris Burkov <boris@bur.io> | 2020-05-27 14:43:19 -0700 |
|---|---|---|
| committer |   Tejun Heo <tj@kernel.org> | 2020-05-28 10:06:35 -0400 |
| commit | 936f2a70f2077f64fab1dcb3eca71879e82ecd3f (patch) | |
| tree | 7a649b1c8e4776ddbada58db00a69b56b9433942 /Documentation/admin-guide | |
| parent | cgroup: Remove stale comments (diff) | |
| download | wireguard-linux-936f2a70f2077f64fab1dcb3eca71879e82ecd3f.tar.xz wireguard-linux-936f2a70f2077f64fab1dcb3eca71879e82ecd3f.zip | |
cgroup: add cpu.stat file to root cgroup
Currently, the root cgroup does not have a cpu.stat file. Add one which
is consistent with /proc/stat to capture global cpu statistics that
might not fall under cgroup accounting.
We haven't done this in the past because the data are already presented
in /proc/stat and we didn't want to add overhead from collecting root
cgroup stats when cgroups are configured, but no cgroups have been
created.
By keeping the data consistent with /proc/stat, I think we avoid the
first problem, while improving the usability of cgroups stats.
We avoid the second problem by computing the contents of cpu.stat from
existing data collected for /proc/stat anyway.
Signed-off-by: Boris Burkov <boris@bur.io>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/cgroup-v2.rst | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index bcc80269bb6a..341a6c2340d5 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -714,9 +714,7 @@ Conventions - Settings for a single feature should be contained in a single file. - The root cgroup should be exempt from resource control and thus - shouldn't have resource control interface files. Also, - informational files on the root cgroup which end up showing global - information available elsewhere shouldn't exist. + shouldn't have resource control interface files. - The default time unit is microseconds. If a different unit is ever used, an explicit unit suffix must be present. @@ -985,7 +983,7 @@ CPU Interface Files All time durations are in microseconds. cpu.stat - A read-only flat-keyed file which exists on non-root cgroups. + A read-only flat-keyed file. This file exists whether the controller is enabled or not. It always reports the following three stats: |