diff options
| author | Yang Shi <yang.shi@linux.alibaba.com> | 2019-01-16 07:51:35 +0800 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2019-01-16 14:51:38 -0700 |
| commit | 053bc5693863d9230f9a11b923ea713aa6a4ce91 (patch) | |
| tree | 2c79ec207e724e37e1b418f91d093e824d14d6b4 | |
| parent | b631c7f513548f4097687603ef6f959ccae18da9 (diff) | |
doc: memcontrol: fix the obsolete content about force empty
We don't do page cache reparent anymore when offlining memcg, so update
force empty related content accordingly.
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
| -rw-r--r-- | Documentation/cgroup-v1/memory.txt | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/Documentation/cgroup-v1/memory.txt b/Documentation/cgroup-v1/memory.txt index 3682e99234c2..8e2cb1dabeb0 100644 --- a/Documentation/cgroup-v1/memory.txt +++ b/Documentation/cgroup-v1/memory.txt @@ -70,7 +70,7 @@ Brief summary of control files. memory.soft_limit_in_bytes # set/show soft limit of memory usage memory.stat # show various statistics memory.use_hierarchy # set/show hierarchical account enabled - memory.force_empty # trigger forced move charge to parent + memory.force_empty # trigger forced page reclaim memory.pressure_level # set memory pressure notifications memory.swappiness # set/show swappiness parameter of vmscan (See sysctl's vm.swappiness) @@ -459,8 +459,9 @@ About use_hierarchy, see Section 6. the cgroup will be reclaimed and as many pages reclaimed as possible. The typical use case for this interface is before calling rmdir(). - Because rmdir() moves all pages to parent, some out-of-use page caches can be - moved to the parent. If you want to avoid that, force_empty will be useful. + Though rmdir() offlines memcg, but the memcg may still stay there due to + charged file caches. Some out-of-use page caches may keep charged until + memory pressure happens. If you want to avoid that, force_empty will be useful. Also, note that when memory.kmem.limit_in_bytes is set the charges due to kernel pages will still be seen. This is not considered a failure and the |