From: Yafang Shao laoar.shao@gmail.com
mainline inclusion from mainline-v5.8-rc1 commit a6f5576bb195c3b7508e3e1c98d2dcf6691f96e8 category: bugfix bugzilla: 34611 CVE: NA
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There's a new workingset counter introduced in commit 1899ad18c607 ("mm: workingset: tell cache transitions from workingset thrashing"). With the help of this counter we can know the workingset is transitioning or thrashing. To leverage the benifit of this counter to memcg, we should introduce it into memory.stat. Then we could know the workingset of the workload inside a memcg better.
Bellow is the verification of this new counter in memory.stat. Read a file into the memory and then read it again to make these pages be active. The size of this file is 1G. (memory.max is greater than file size) The counters in memory.stat will be
inactive_file 0 active_file 1073639424
workingset_refault 0 workingset_activate 0 workingset_restore 0 workingset_nodereclaim 0
Trigger the memcg reclaim by setting a lower value to memory.high, and then some pages will be demoted into inactive list, and then some pages in the inactive list will be evicted into the storage.
inactive_file 498094080 active_file 310063104
workingset_refault 0 workingset_activate 0 workingset_restore 0 workingset_nodereclaim 0
Then recover the memory.high and read the file into memory again. As a result of it, the transitioning will occur. Bellow is the result of this transitioning,
inactive_file 498094080 active_file 575397888
workingset_refault 64746 workingset_activate 64746 workingset_restore 64746 workingset_nodereclaim 0
Signed-off-by: Yafang Shao laoar.shao@gmail.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Acked-by: Johannes Weiner hannes@cmpxchg.org Acked-by: Michal Hocko mhocko@suse.com Acked-by: Chris Down chris@chrisdown.name Cc: Peter Zijlstra (Intel) peterz@infradead.org Cc: Suren Baghdasaryan surenb@google.com Cc: Shakeel Butt shakeelb@google.com Link: http://lkml.kernel.org/r/20200504153522.11553-1-laoar.shao@gmail.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Liu Shixin liushixin2@huawei.com Reviewed-by: Kefeng Wang wangkefeng.wang@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- Documentation/admin-guide/cgroup-v2.rst | 4 ++++ mm/memcontrol.c | 2 ++ 2 files changed, 6 insertions(+)
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 8305db50fa04..8c1fe548fee8 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1214,6 +1214,10 @@ PAGE_SIZE multiple when read back.
Number of refaulted pages that were immediately activated
+ workingset_restore + Number of restored pages which have been detected as an active + workingset before they got reclaimed. + workingset_nodereclaim
Number of times a shadow node has been reclaimed diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9c7d4aff03d1..336498908b2d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5991,6 +5991,8 @@ static int memory_stat_show(struct seq_file *m, void *v) memcg_page_state(memcg, WORKINGSET_REFAULT)); seq_printf(m, "workingset_activate %lu\n", memcg_page_state(memcg, WORKINGSET_ACTIVATE)); + seq_printf(m, "workingset_restore %lu\n", + memcg_page_state(memcg, WORKINGSET_RESTORE)); seq_printf(m, "workingset_nodereclaim %lu\n", memcg_page_state(memcg, WORKINGSET_NODERECLAIM));