From: Mel Gorman Date: Tue, 22 Sep 2009 00:02:31 +0000 (-0700) Subject: page-allocator: change migratetype for all pageblocks within a high-order page during... X-Git-Tag: v2.6.32-rc1~534 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2f66a68f3fac2e94da360c342ff78ab45553f86c;p=pandora-kernel.git 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 Cc: Andy Whitcroft Cc: KOSAKI Motohiro Cc: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed