path: root/Documentation/cgroups
diff options
authorBalbir Singh <balbir@linux.vnet.ibm.com>2009-09-23 15:56:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-24 07:20:58 -0700
commit4b3bde4c983de36c59e6c1a24701f6fe816f9f55 (patch)
treee759c5ceccf57331b868b7feac61cae5e932c6d4 /Documentation/cgroups
parentbe367d09927023d081f9199665c8500f69f14d22 (diff)
memcg: remove the overhead associated with the root cgroup
Change the memory cgroup to remove the overhead associated with accounting all pages in the root cgroup. As a side-effect, we can no longer set a memory hard limit in the root cgroup. A new flag to track whether the page has been accounted or not has been added as well. Flags are now set atomically for page_cgroup, pcg_default_flags is now obsolete and removed. [akpm@linux-foundation.org: fix a few documentation glitches] Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/cgroups')
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
index 23d1262c077..ab0a02172cf 100644
--- a/Documentation/cgroups/memory.txt
+++ b/Documentation/cgroups/memory.txt
@@ -179,6 +179,9 @@ The reclaim algorithm has not been modified for cgroups, except that
pages that are selected for reclaiming come from the per cgroup LRU
+NOTE: Reclaim does not work for the root cgroup, since we cannot set any
+limits on the root cgroup.
2. Locking
The memory controller uses the following hierarchy
@@ -210,6 +213,7 @@ We can alter the memory limit:
NOTE: We can use a suffix (k, K, m, M, g or G) to indicate values in kilo,
mega or gigabytes.
NOTE: We can write "-1" to reset the *.limit_in_bytes(unlimited).
+NOTE: We cannot set limits on the root cgroup any more.
# cat /cgroups/0/memory.limit_in_bytes