Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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>
authored by
Yang Shi
and committed by
Jonathan Corbet
053bc569
b631c7f5
+4
-3
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-3
Documentation/cgroup-v1/memory.txt
+4
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Documentation/cgroup-v1/memory.txt
···
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memory.soft_limit_in_bytes # set/show soft limit of memory usage
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memory.stat # show various statistics
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memory.use_hierarchy # set/show hierarchical account enabled
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memory.force_empty # trigger forced move charge to parent
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memory.force_empty # trigger forced page reclaim
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memory.pressure_level # set memory pressure notifications
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memory.swappiness # set/show swappiness parameter of vmscan
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(See sysctl's vm.swappiness)
···
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the cgroup will be reclaimed and as many pages reclaimed as possible.
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The typical use case for this interface is before calling rmdir().
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Because rmdir() moves all pages to parent, some out-of-use page caches can be
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moved to the parent. If you want to avoid that, force_empty will be useful.
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Though rmdir() offlines memcg, but the memcg may still stay there due to
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charged file caches. Some out-of-use page caches may keep charged until
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memory pressure happens. If you want to avoid that, force_empty will be useful.
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Also, note that when memory.kmem.limit_in_bytes is set the charges due to
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kernel pages will still be seen. This is not considered a failure and the