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authorJiri Kosina <jkosina@suse.cz>2019-11-29 22:34:28 +0300
committerJiri Kosina <jkosina@suse.cz>2019-11-29 22:34:28 +0300
commitb746a1a2860f4a918f32d10dc569115d282aaf2f (patch)
tree4b30e6ff28e2783c73a1b763e819f5b41414563c /Documentation/admin-guide/cgroup-v2.rst
parent8725aa4fa7ded30211ebd28bb1c9bae806eb3841 (diff)
parentb03e5774d51fe003e1020060c403a1d085b128eb (diff)
downloadlinux-b746a1a2860f4a918f32d10dc569115d282aaf2f.tar.xz
Merge branch 'for-5.5/core' into for-linus
- hid_have_special_driver[] cleanup for LED devices (Heiner Kallweit) - HID parser improvements (Blaž Hrastnik, Candle Sun)
Diffstat (limited to 'Documentation/admin-guide/cgroup-v2.rst')
-rw-r--r--Documentation/admin-guide/cgroup-v2.rst20
1 files changed, 14 insertions, 6 deletions
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 0fa8c0e615c2..5361ebec3361 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -615,8 +615,8 @@ on an IO device and is an example of this type.
Protections
-----------
-A cgroup is protected to be allocated upto the configured amount of
-the resource if the usages of all its ancestors are under their
+A cgroup is protected upto the configured amount of the resource
+as long as the usages of all its ancestors are under their
protected levels. Protections can be hard guarantees or best effort
soft boundaries. Protections can also be over-committed in which case
only upto the amount available to the parent is protected among
@@ -1096,7 +1096,10 @@ PAGE_SIZE multiple when read back.
is within its effective min boundary, the cgroup's memory
won't be reclaimed under any conditions. If there is no
unprotected reclaimable memory available, OOM killer
- is invoked.
+ is invoked. Above the effective min boundary (or
+ effective low boundary if it is higher), pages are reclaimed
+ proportionally to the overage, reducing reclaim pressure for
+ smaller overages.
Effective min boundary is limited by memory.min values of
all ancestor cgroups. If there is memory.min overcommitment
@@ -1118,7 +1121,10 @@ PAGE_SIZE multiple when read back.
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.
+ from unprotected cgroups. Above the effective low boundary (or
+ effective min boundary if it is higher), pages are reclaimed
+ proportionally to the overage, reducing reclaim pressure for
+ smaller overages.
Effective low boundary is limited by memory.low values of
all ancestor cgroups. If there is memory.low overcommitment
@@ -2482,8 +2488,10 @@ system performance due to overreclaim, to the point where the feature
becomes self-defeating.
The memory.low boundary on the other hand is a top-down allocated
-reserve. A cgroup enjoys reclaim protection when it's within its low,
-which makes delegation of subtrees possible.
+reserve. A cgroup enjoys reclaim protection when it's within its
+effective low, which makes delegation of subtrees possible. It also
+enjoys having reclaim pressure proportional to its overage when
+above its effective low.
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.