memcg: update menuconfig help text

page_cgroup is now allocated at boot and memmap doesn't includes pointer
for page_cgroup.  Fix the menu help text.

Reviewed-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: KAMEZAWA hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
KAMEZAWA Hiroyuki 2008-10-29 14:01:06 -07:00 committed by Linus Torvalds
parent 99e87fd19a
commit 84ad6d7000

View File

@ -401,16 +401,20 @@ config CGROUP_MEM_RES_CTLR
depends on CGROUPS && RESOURCE_COUNTERS
select MM_OWNER
help
Provides a memory resource controller that manages both page cache and
RSS memory.
Provides a memory resource controller that manages both anonymous
memory and page cache. (See Documentation/controllers/memory.txt)
Note that setting this option increases fixed memory overhead
associated with each page of memory in the system by 4/8 bytes
and also increases cache misses because struct page on many 64bit
systems will not fit into a single cache line anymore.
associated with each page of memory in the system. By this,
20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
usage tracking struct at boot. Total amount of this is printed out
at boot.
Only enable when you're ok with these trade offs and really
sure you need the memory resource controller.
sure you need the memory resource controller. Even when you enable
this, you can set "cgroup_disable=memory" at your boot option to
disable memory resource controller and you can avoid overheads.
(and lose benefits of memory resource contoller)
This config option also selects MM_OWNER config option, which
could in turn add some fork/exit overhead.