mm: add overcommit_kbytes sysctl variable
authorJerome Marchand <jmarchan@redhat.com>
Tue, 21 Jan 2014 23:49:14 +0000 (15:49 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 22 Jan 2014 00:19:44 +0000 (16:19 -0800)
commit49f0ce5f92321cdcf741e35f385669a421013cb7
treed41c5a2283b32be69840cb8722ffd8cd8c38a1b0
parentaec6a8889a98a0cd58357cd0937a25189908f191
mm: add overcommit_kbytes sysctl variable

Some applications that run on HPC clusters are designed around the
availability of RAM and the overcommit ratio is fine tuned to get the
maximum usage of memory without swapping.  With growing memory, the
1%-of-all-RAM grain provided by overcommit_ratio has become too coarse
for these workload (on a 2TB machine it represents no less than 20GB).

This patch adds the new overcommit_kbytes sysctl variable that allow a
much finer grain.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix nommu build]
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Documentation/sysctl/vm.txt
Documentation/vm/overcommit-accounting
include/linux/mm.h
include/linux/mman.h
kernel/sysctl.c
mm/mmap.c
mm/nommu.c
mm/util.c