From: Mel Gorman Date: Tue, 10 Aug 2010 00:19:18 +0000 (-0700) Subject: vmscan: tracing: add trace event when a page is written X-Git-Tag: v2.6.36-rc1~425 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=755f0225e8347b23a33ee6e3fb14a35310f95766;p=pandora-kernel.git vmscan: tracing: add trace event when a page is written Add a trace event for when page reclaim queues a page for IO and records whether it is synchronous or asynchronous. Excessive synchronous IO for a process can result in noticeable stalls during direct reclaim. Excessive IO from page reclaim may indicate that the system is seriously under provisioned for the amount of dirty pages that exist. Signed-off-by: Mel Gorman Acked-by: Rik van Riel Acked-by: Larry Woodman Cc: Dave Chinner Cc: Chris Mason Cc: Nick Piggin Cc: Rik van Riel Cc: Johannes Weiner Cc: Christoph Hellwig Cc: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro Cc: Andrea Arcangeli Cc: Michael Rubin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed