linux/Documentation/vm
Lee Schermerhorn fc36b8d3d8 mempolicy: use MPOL_F_LOCAL to Indicate Preferred Local Policy
Now that we're using "preferred local" policy for system default, we need to
make this as fast as possible.  Because of the variable size of the mempolicy
structure [based on size of nodemasks], the preferred_node may be in a
different cacheline from the mode.  This can result in accessing an extra
cacheline in the normal case of system default policy.  Suspect this is the
cause of an observed 2-3% slowdown in page fault testing relative to kernel
without this patch series.

To alleviate this, use an internal mode flag, MPOL_F_LOCAL in the mempolicy
flags member which is guaranteed [?] to be in the same cacheline as the mode
itself.

Verified that reworked mempolicy now performs slightly better on 25-rc8-mm1
for both anon and shmem segments with system default and vma [preferred local]
policy.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:24 -07:00
..
00-INDEX doc: move vm/00-INDEX to Documentation/vm 2007-10-17 08:43:05 -07:00
balance
hugetlbpage.txt Documentation: correct overcommit caveat in hugetlbpage.txt 2008-04-15 19:35:41 -07:00
locking
numa Documentation: remove duplicated words 2006-10-03 22:57:56 +02:00
numa_memory_policy.txt mempolicy: use MPOL_F_LOCAL to Indicate Preferred Local Policy 2008-04-28 08:58:24 -07:00
overcommit-accounting
page_migration [PATCH] page migration: sys_move_pages(): support moving of individual pages 2006-06-23 07:42:53 -07:00
slabinfo.c slabinfo: fall back from /sys/kernel/slab to /sys/slab 2008-02-21 15:27:06 -08:00
slub.txt slub: fix typo in Documentation/vm/slub.txt 2008-03-06 16:21:50 -08:00