cgroup memory controller: document huge memory/cache overhead in Kconfig
commit0835ab53eab5bbeebe1c135e92fb0c4d483dde17
authorAndi Kleen <andi@firstfloor.org>
Sat, 23 Feb 2008 23:24:02 +0000 (23 15:24 -0800)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Sun, 24 Feb 2008 01:12:16 +0000 (23 17:12 -0800)
tree037ce3a4885d46cfba34a4265bead1d081d2814b
parent00d6296145c6b671a9886e380efc24f2731d856a
cgroup memory controller: document huge memory/cache overhead in Kconfig

Document huge memory/cache overhead of memory controller in Kconfig

I was a little surprised that 2.6.25-rc* increased struct page for the
memory controller.  At least on many x86-64 machines it will not fit into a
single cache line now anymore and also costs considerable amounts of RAM.
At earlier review I remembered asking for a external data structure for
this.

It's also quite unobvious that a innocent looking Kconfig option with a
single line Kconfig description has such a negative effect.

This patch attempts to document these disadvantages at least so that users
configuring their kernel can make a informed decision.

Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Balbir Singh <balbir@in.ibm.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
init/Kconfig