1
linux/Documentation/cgroups
Daniel Lezcano a77aea9201 cgroup: remove the ns_cgroup
The ns_cgroup is an annoying cgroup at the namespace / cgroup frontier and
leads to some problems:

  * cgroup creation is out-of-control
  * cgroup name can conflict when pids are looping
  * it is not possible to have a single process handling a lot of
    namespaces without falling in a exponential creation time
  * we may want to create a namespace without creating a cgroup

  The ns_cgroup was replaced by a compatibility flag 'clone_children',
  where a newly created cgroup will copy the parent cgroup values.
  The userspace has to manually create a cgroup and add a task to
  the 'tasks' file.

This patch removes the ns_cgroup as suggested in the following thread:

https://lists.linux-foundation.org/pipermail/containers/2009-June/018616.html

The 'cgroup_clone' function is removed because it is no longer used.

This is a userspace-visible change.  Commit 45531757b4 ("cgroup: notify
ns_cgroup deprecated") (merged into 2.6.27) caused the kernel to emit a
printk warning users that the feature is planned for removal.  Since that
time we have heard from XXX users who were affected by this.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jamal Hadi Salim <hadi@cyberus.ca>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:34 -07:00
..
00-INDEX
blkio-controller.txt blk-cgroup: Lower minimum weight from 100 to 10. 2011-03-08 19:45:00 +01:00
cgroup_event_listener.c tree-wide: fix comment/printk typos 2010-11-01 15:38:34 -04:00
cgroups.txt cgroup: remove the ns_cgroup 2011-05-26 17:12:34 -07:00
cpuacct.txt
cpusets.txt Update cpuset info & webiste for cgroups 2011-03-08 23:12:39 +01:00
devices.txt
freezer-subsystem.txt
memcg_test.txt tree-wide: fix comment/printk typos 2010-11-01 15:38:34 -04:00
memory.txt memcg: update documentation to describe usage_in_bytes 2011-04-28 11:28:21 -07:00
resource_counter.txt