From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wu Fengguang Subject: [PATCH 18/18] btrfs: fix dirtied pages accounting on sub-page writes Date: Sun, 04 Sep 2011 09:53:23 +0800 Message-ID: <20110904020916.972004786@intel.com> References: <20110904015305.367445271@intel.com> Cc: Peter Zijlstra , Chris Mason , Wu Fengguang To: Return-path: cc: Andrew Morton CC: Jan Kara CC: Christoph Hellwig CC: Dave Chinner CC: Greg Thelen CC: Minchan Kim CC: Vivek Goyal CC: Andrea Righi Cc: linux-mm Cc: LKML Content-Disposition: inline; filename=btrfs-account-redirty Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org When doing 1KB sequential writes to the same page, balance_dirty_pages_ratelimited_nr() should be called once instead of 4 times, the latter makes the dirtier tasks be throttled much too heavy. Fix it with proper de-accounting on clear_page_dirty_for_io(). CC: Chris Mason Signed-off-by: Wu Fengguang --- fs/btrfs/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- linux-next.orig/fs/btrfs/file.c 2011-08-29 19:14:32.000000000 +0800 +++ linux-next/fs/btrfs/file.c 2011-08-29 19:14:40.000000000 +0800 @@ -1138,7 +1138,8 @@ again: GFP_NOFS); } for (i = 0; i < num_pages; i++) { - clear_page_dirty_for_io(pages[i]); + if (clear_page_dirty_for_io(pages[i])) + account_page_redirty(pages[i]); set_page_extent_mapped(pages[i]); WARN_ON(!PageLocked(pages[i])); } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org