+ mm-docs-describe-memorylow-refinements.patch added to -mm tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The patch titled
     Subject: mm/docs: describe memory.low refinements
has been added to the -mm tree.  Its filename is
     mm-docs-describe-memorylow-refinements.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/mm-docs-describe-memorylow-refinements.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/mm-docs-describe-memorylow-refinements.patch

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next and is updated
there every 3-4 working days

------------------------------------------------------
From: Roman Gushchin <guro@xxxxxx>
Subject: mm/docs: describe memory.low refinements

Refine cgroup v2 docs after latest memory.low changes.

Link: http://lkml.kernel.org/r/20180405185921.4942-4-guro@xxxxxx
Signed-off-by: Roman Gushchin <guro@xxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 Documentation/cgroup-v2.txt |   28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff -puN Documentation/cgroup-v2.txt~mm-docs-describe-memorylow-refinements Documentation/cgroup-v2.txt
--- a/Documentation/cgroup-v2.txt~mm-docs-describe-memorylow-refinements
+++ a/Documentation/cgroup-v2.txt
@@ -1005,10 +1005,17 @@ PAGE_SIZE multiple when read back.
 	A read-write single value file which exists on non-root
 	cgroups.  The default is "0".
 
-	Best-effort memory protection.  If the memory usages of a
-	cgroup and all its ancestors are below their low boundaries,
-	the cgroup's memory won't be reclaimed unless memory can be
-	reclaimed from unprotected cgroups.
+	Best-effort memory protection.  If the memory usage of a
+	cgroup is within its effective low boundary, the cgroup's
+	memory won't be reclaimed unless memory can be reclaimed
+	from unprotected cgroups.
+
+	Effective low boundary is limited by memory.low values of
+	all ancestor cgroups. If there is memory.low overcommitment
+	(child cgroup or cgroups are requiring more protected memory,
+	than parent will allow), then each child cgroup will get
+	the part of parent's protection proportional to the its
+	actual memory usage below memory.low.
 
 	Putting more memory than generally available under this
 	protection is discouraged.
@@ -1950,17 +1957,8 @@ system performance due to overreclaim, t
 becomes self-defeating.
 
 The memory.low boundary on the other hand is a top-down allocated
-reserve.  A cgroup enjoys reclaim protection when it and all its
-ancestors are below their low boundaries, which makes delegation of
-subtrees possible.  Secondly, new cgroups have no reserve per default
-and in the common case most cgroups are eligible for the preferred
-reclaim pass.  This allows the new low boundary to be efficiently
-implemented with just a minor addition to the generic reclaim code,
-without the need for out-of-band data structures and reclaim passes.
-Because the generic reclaim code considers all cgroups except for the
-ones running low in the preferred first reclaim pass, overreclaim of
-individual groups is eliminated as well, resulting in much better
-overall workload performance.
+reserve.  A cgroup enjoys reclaim protection when it's within its low,
+which makes delegation of subtrees possible.
 
 The original high boundary, the hard limit, is defined as a strict
 limit that can not budge, even if the OOM killer has to be called.
_

Patches currently in -mm which might be from guro@xxxxxx are

mm-rename-page_counters-count-limit-into-usage-max.patch
mm-memorylow-hierarchical-behavior.patch
mm-treat-memorylow-value-inclusive.patch
mm-docs-describe-memorylow-refinements.patch
mm-oom-refactor-the-oom_kill_process-function.patch
mm-implement-mem_cgroup_scan_tasks-for-the-root-memory-cgroup.patch
mm-oom-cgroup-aware-oom-killer.patch
mm-oom-introduce-memoryoom_group.patch
mm-oom-introduce-memoryoom_group-fix.patch
mm-oom-add-cgroup-v2-mount-option-for-cgroup-aware-oom-killer.patch
mm-oom-docs-describe-the-cgroup-aware-oom-killer.patch
mm-oom-docs-describe-the-cgroup-aware-oom-killer-fix.patch
cgroup-list-groupoom-in-cgroup-features.patch

--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Kernel Archive]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]

  Powered by Linux