linux-toradex.git/Documentation/cgroups/memory.txt, branch v3.0.79

Documentation: fix cgroup typos and formatting

2011-06-16T04:52:50+00:00

Fix format and spelling.

Signed-off-by: Jörg Sommer 
Acked-by: Paul Menage 
Signed-off-by: Randy Dunlap 
Signed-off-by: Linus Torvalds

Documentation: update cgroupfs mount point

2011-06-16T04:52:50+00:00

According to commit 676db4af0430 ("cgroupfs: create /sys/fs/cgroup to
mount cgroupfs on") the canonical mountpoint for the cgroup filesystem
is /sys/fs/cgroup.  Hence, this should be used in the documentation.

Signed-off-by: Jörg Sommer 
Acked-by: Paul Menage 
Signed-off-by: Randy Dunlap 
Signed-off-by: Linus Torvalds

memcg: add documentation for the memory.numastat API

2011-06-16T03:03:59+00:00

[akpm@linux-foundation.org: rework text, fit it into 80-cols]
Signed-off-by: Ying Han 
Reviewed-by: KOSAKI Motohiro 
Acked-by: Balbir Singh 
Acked-by: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: update documentation to describe usage_in_bytes

2011-04-28T18:28:21+00:00

Since 569b846d ("memcg: coalesce uncharge during unmap/truncate"), we do
batched (delayed) uncharge at truncation/unmap.  And since cdec2e42(memcg:
coalesce charging via percpu storage), we have percpu cache for
res_counter.

These changes improved performance of memory cgroup very much, but made
res_counter->usage usually have a bigger value than the actual value of
memory usage.  So, *.usage_in_bytes, which show res_counter->usage, are
not desirable for precise values of memory(and swap) usage anymore.

Instead of removing these files completely(because we cannot know
res_counter->usage without them), this patch updates the meaning of those
files.

Signed-off-by: Daisuke Nishimura 
Acked-by: KAMEZAWA Hiroyuki 
Acked-by: Michal Hocko 
Cc: Balbir Singh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: clarify use_hierarchy documentation

2011-02-17T08:17:21+00:00

The memcg code does not allow changing memory.use_hierarchy if the
parent cgroup has enabled use_hierarchy.  Update documentation to match
the code.

Signed-off-by: Greg Thelen 
Acked-by: KAMEZAWA Hiroyuki 
Signed-off-by: Jiri Kosina

memcg: update documentation

2010-05-27T16:12:43+00:00

Some information are old, and I think current document doesn't work as "a
guide for users".  We need summary of all of our controls, at least.

Signed-off-by: KAMEZAWA Hiroyuki 
Reviewed-by: Randy Dunlap 
Cc: Balbir Singh 
Cc: Daisuke Nishimura 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: move charge of file pages

2010-05-27T16:12:43+00:00

This patch adds support for moving charge of file pages, which include
normal file, tmpfs file and swaps of tmpfs file.  It's enabled by setting
bit 1 of /memory.move_charge_at_immigrate.

Unlike the case of anonymous pages, file pages(and swaps) in the range
mmapped by the task will be moved even if the task hasn't done page fault,
i.e.  they might not be the task's "RSS", but other task's "RSS" that maps
the same file.  And mapcount of the page is ignored(the page can be moved
even if page_mapcount(page) > 1).  So, conditions that the page/swap
should be met to be moved is that it must be in the range mmapped by the
target task and it must be charged to the old cgroup.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix warning]
Signed-off-by: Daisuke Nishimura 
Acked-by: KAMEZAWA Hiroyuki 
Cc: Balbir Singh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: oom kill disable and oom status

2010-05-27T16:12:43+00:00

This adds a feature to disable oom-killer for memcg, if disabled, of
course, tasks under memcg will stop.

But now, we have oom-notifier for memcg.  And the world around memcg is
not under out-of-memory.  memcg's out-of-memory just shows memcg hits
limit.  Then, administrator or management daemon can recover the situation
by

	- kill some process
	- enlarge limit, add more swap.
	- migrate some tasks
	- remove file cache on tmps (difficult ?)

Unlike oom-killer, you can take enough information before killing tasks.
(by gcore, or, ps etc.)

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki 
Cc: Daisuke Nishimura 
Cc: Balbir Singh 
Cc: Daisuke Nishimura 
Cc: David Rientjes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: oom notifier

2010-05-27T16:12:43+00:00

Considering containers or other resource management softwares in userland,
event notification of OOM in memcg should be implemented.  Now, memcg has
"threshold" notifier which uses eventfd, we can make use of it for oom
notification.

This patch adds oom notification eventfd callback for memcg.  The usage is
very similar to threshold notifier, but control file is memory.oom_control
and no arguments other than eventfd is required.

	% cgroup_event_notifier /cgroup/A/memory.oom_control dummy
	(About cgroup_event_notifier, see Documentation/cgroup/)

Signed-off-by: KAMEZAWA Hiroyuki 
Cc: Daisuke Nishimura 
Cc: Balbir Singh 
Cc: Daisuke Nishimura 
Cc: David Rientjes 
Cc: Davide Libenzi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Documentation/: it's -> its where appropriate

2010-04-23T00:09:52+00:00

Fix obvious cases of "it's" being used when "its" was meant.

Signed-off-by: Francis Galiegue 
Acked-by: Randy Dunlap 
Signed-off-by: Jiri Kosina