This has confused a significant number of people using cgroups inside Facebook, and some of those outside as well judging by posts like this[0] (although it's not a problem unique to cgroup v2). If shmem handling in particular becomes more coherent at some point in the future -- although that seems unlikely now -- we can change the wording here. [0]: https://unix.stackexchange.com/q/525092/10762 Signed-off-by: Chris Down <chris@xxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> Cc: Roman Gushchin <guro@xxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: cgroups@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: kernel-team@xxxxxx --- Documentation/admin-guide/cgroup-v2.rst | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 0704552ed94f..0636bcb60b5a 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1289,7 +1289,12 @@ PAGE_SIZE multiple when read back. inactive_anon, active_anon, inactive_file, active_file, unevictable Amount of memory, swap-backed and filesystem-backed, on the internal memory management lists used by the - page reclaim algorithm + page reclaim algorithm. + + As these represent internal list state (eg. shmem pages are on anon + memory management lists), inactive_foo + active_foo may not be equal to + the value for the foo counter, since the foo counter is type-based, not + list-based. slab_reclaimable Part of "slab" that might be reclaimed, such as -- 2.24.0