diff options
author | Dan Schatzberg | 2022-01-14 14:05:35 -0800 |
---|---|---|
committer | Linus Torvalds | 2022-01-15 16:30:27 +0200 |
commit | b6bf9abb0aa44e53ffe9c1e6e1d32568f5b25e4a (patch) | |
tree | 37e8bbfbd7190d423841033b705cb5704626ed0b /Documentation/admin-guide/cgroup-v2.rst | |
parent | 46a53371f3fd9bf873fdd9c4df75b1cd86df1098 (diff) |
mm/memcg: add oom_group_kill memory event
Our container agent wants to know when a container exits if it was OOM
killed or not to report to the user. We use memory.oom.group = 1 to
ensure that OOM kills within the container's cgroup kill everything.
Existing memory.events are insufficient for knowing if this triggered:
1) Our current approach reads memory.events oom_kill and reports the
container was killed if the value is non-zero. This is erroneous in
some cases where containers create their children cgroups with
memory.oom.group=1 as such OOM kills will get counted against the
container cgroup's oom_kill counter despite not actually OOM killing
the entire container.
2) Reading memory.events.local will fail to identify OOM kills in leaf
cgroups (that don't set memory.oom.group) within the container
cgroup.
This patch adds a new oom_group_kill event when memory.oom.group
triggers to allow userspace to cleanly identify when an entire cgroup is
oom killed.
[schatzberg.dan@gmail.com: changes from Johannes and Chris]
Link: https://lkml.kernel.org/r/20211213162511.2492267-1-schatzberg.dan@gmail.com
Link: https://lkml.kernel.org/r/20211203162426.3375036-1-schatzberg.dan@gmail.com
Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/admin-guide/cgroup-v2.rst')
-rw-r--r-- | Documentation/admin-guide/cgroup-v2.rst | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 2aeb7ae8b393..8269bfa240f4 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1268,6 +1268,9 @@ PAGE_SIZE multiple when read back. The number of processes belonging to this cgroup killed by any kind of OOM killer. + oom_group_kill + The number of times a group OOM has occurred. + memory.events.local Similar to memory.events but the fields in the file are local to the cgroup i.e. not hierarchical. The file modified event |