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* [PATCH v2 0/3] mm: memcontrol: recursive memory protection
@ 2019-12-19 20:07 Johannes Weiner
  2019-12-19 20:07 ` [PATCH v2 1/3] mm: memcontrol: fix memory.low proportional distribution Johannes Weiner
                   ` (5 more replies)
  0 siblings, 6 replies; 52+ messages in thread
From: Johannes Weiner @ 2019-12-19 20:07 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Roman Gushchin, Michal Hocko, Tejun Heo, linux-mm, cgroups,
	linux-kernel, kernel-team

Changes since v1:
- improved Changelogs based on the discussion with Roman. Thanks!
- fix div0 when recursive & fixed protection is combined
- fix an unused compiler warning

The current memory.low (and memory.min) semantics require protection
to be assigned to a cgroup in an untinterrupted chain from the
top-level cgroup all the way to the leaf.

In practice, we want to protect entire cgroup subtrees from each other
(system management software vs. workload), but we would like the VM to
balance memory optimally *within* each subtree, without having to make
explicit weight allocations among individual components. The current
semantics make that impossible.

This patch series extends memory.low/min such that the knobs apply
recursively to the entire subtree. Users can still assign explicit
protection to subgroups, but if they don't, the protection set by the
parent cgroup will be distributed dynamically such that children
compete freely - as if no memory control were enabled inside the
subtree - but enjoy protection from neighboring trees.

Patch #1 fixes an existing bug that can give a cgroup tree more
protection than it should receive as per ancestor configuration.

Patch #2 simplifies and documents the existing code to make it easier
to reason about the changes in the next patch.

Patch #3 finally implements recursive memory protection semantics.

Because of a risk of regressing legacy setups, the new semantics are
hidden behind a cgroup2 mount option, 'memory_recursiveprot'.

More details in patch #3.

 Documentation/admin-guide/cgroup-v2.rst |  11 ++
 include/linux/cgroup-defs.h             |   5 +
 kernel/cgroup/cgroup.c                  |  17 ++-
 mm/memcontrol.c                         | 243 +++++++++++++++++++-----------
 mm/page_counter.c                       |  12 +-
 5 files changed, 192 insertions(+), 96 deletions(-)




^ permalink raw reply	[flat|nested] 52+ messages in thread

end of thread, other threads:[~2020-02-27 15:19 UTC | newest]

Thread overview: 52+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-12-19 20:07 [PATCH v2 0/3] mm: memcontrol: recursive memory protection Johannes Weiner
2019-12-19 20:07 ` [PATCH v2 1/3] mm: memcontrol: fix memory.low proportional distribution Johannes Weiner
2020-01-30 11:49   ` Michal Hocko
2020-02-03 21:21     ` Johannes Weiner
2020-02-03 21:38       ` Roman Gushchin
2019-12-19 20:07 ` [PATCH v2 2/3] mm: memcontrol: clean up and document effective low/min calculations Johannes Weiner
2020-01-30 12:54   ` Michal Hocko
2020-02-21 17:10   ` Michal Koutný
2020-02-25 18:40     ` Johannes Weiner
2020-02-26 16:46       ` Michal Koutný
2020-02-26 19:40         ` Johannes Weiner
2019-12-19 20:07 ` [PATCH v2 3/3] mm: memcontrol: recursive memory.low protection Johannes Weiner
2020-01-30 17:00   ` Michal Hocko
2020-02-03 21:52     ` Johannes Weiner
2020-02-10 15:21       ` Johannes Weiner
2020-02-11 16:47       ` Michal Hocko
2020-02-12 17:08         ` Johannes Weiner
2020-02-13  7:40           ` Michal Hocko
2020-02-13 13:23             ` Johannes Weiner
2020-02-13 15:46               ` Michal Hocko
2020-02-13 17:41                 ` Johannes Weiner
2020-02-13 17:58                   ` Johannes Weiner
2020-02-14  7:59                     ` Michal Hocko
2020-02-13 13:53             ` Tejun Heo
2020-02-13 15:47               ` Michal Hocko
2020-02-13 15:52                 ` Tejun Heo
2020-02-13 16:36                   ` Michal Hocko
2020-02-13 16:57                     ` Tejun Heo
2020-02-14  7:15                       ` Michal Hocko
2020-02-14 13:57                         ` Tejun Heo
2020-02-14 15:13                           ` Michal Hocko
2020-02-14 15:40                             ` Tejun Heo
2020-02-14 16:53                             ` Johannes Weiner
2020-02-14 17:17                               ` Tejun Heo
2020-02-17  8:41                               ` Michal Hocko
2020-02-18 19:52                                 ` Johannes Weiner
2020-02-21 10:11                                   ` Michal Hocko
2020-02-21 15:43                                     ` Johannes Weiner
2020-02-25 12:20                                       ` Michal Hocko
2020-02-25 18:17                                         ` Johannes Weiner
2020-02-26 17:56                                           ` Michal Hocko
2020-02-21 17:12   ` Michal Koutný
2020-02-21 18:58     ` Johannes Weiner
2020-02-25 13:37       ` Michal Koutný
2020-02-25 15:03         ` Johannes Weiner
2020-02-26 13:22           ` Michal Koutný
2020-02-26 15:05             ` Johannes Weiner
2020-02-27 13:35               ` Michal Koutný
2020-02-27 15:06                 ` Johannes Weiner
2019-12-19 20:22 ` [PATCH v2 0/3] mm: memcontrol: recursive memory protection Tejun Heo
2019-12-20  4:06 ` Roman Gushchin
2019-12-20  4:29 ` Chris Down

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