diff options
| author | Mel Gorman <mel@csn.ul.ie> | 2009-09-21 17:02:31 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-22 07:17:33 -0700 |
| commit | 2f66a68f3fac2e94da360c342ff78ab45553f86c (patch) | |
| tree | ec8de9c7d18d866e63e2c9bcbecf902896b687bd /mm/vmalloc.c | |
| parent | fe1ff49d0d1c30254dbfc84c3786eb538e0cc7d1 (diff) | |
page-allocator: change migratetype for all pageblocks within a high-order page during __rmqueue_fallback
When there are no pages of a target migratetype free, the page allocator
selects a high-order block of another migratetype to allocate from. When
the order of the page taken is greater than pageblock_order, all
pageblocks within that high-order page should change migratetype so that
pages are later freed to the correct free-lists.
The current behaviour is that pageblocks change migratetype if the order
being split matches the pageblock_order. When pageblock_order <
MAX_ORDER-1, ownership is not changing correct and pages are being later
freed to the incorrect list and this impacts fragmentation avoidance.
This patch changes all pageblocks within the high-order page being split
to the correct migratetype. Without the patch, allocation success rates
for hugepages under stress were about 59% of physical memory on x86-64.
With the patch applied, this goes up to 65%.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: 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>
Diffstat (limited to 'mm/vmalloc.c')
0 files changed, 0 insertions, 0 deletions