From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id EF88D8D003A for ; Thu, 3 Mar 2011 03:17:55 -0500 (EST) Message-Id: <20110303074949.165618203@intel.com> Date: Thu, 03 Mar 2011 14:45:09 +0800 From: Wu Fengguang Subject: [PATCH 04/27] writeback: reduce per-bdi dirty threshold ramp up time References: <20110303064505.718671603@intel.com> Content-Disposition: inline; filename=writeback-speedup-per-bdi-threshold-ramp-up.patch Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Jan Kara , Peter Zijlstra , Richard Kennedy , Wu Fengguang , Christoph Hellwig , Trond Myklebust , Dave Chinner , Theodore Ts'o , Chris Mason , Mel Gorman , Rik van Riel , KOSAKI Motohiro , Greg Thelen , Minchan Kim , Vivek Goyal , Andrea Righi , Balbir Singh , linux-mm , linux-fsdevel@vger.kernel.org, LKML Reduce the dampening for the control system, yielding faster convergence. The change is a bit conservative, as smaller values may lead to noticeable bdi threshold fluctuates in low memory JBOD setup. CC: Peter Zijlstra CC: Richard Kennedy Signed-off-by: Wu Fengguang --- mm/page-writeback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- linux-next.orig/mm/page-writeback.c 2011-03-02 14:52:19.000000000 +0800 +++ linux-next/mm/page-writeback.c 2011-03-02 15:00:17.000000000 +0800 @@ -145,7 +145,7 @@ static int calc_period_shift(void) else dirty_total = (vm_dirty_ratio * determine_dirtyable_memory()) / 100; - return 2 + ilog2(dirty_total - 1); + return ilog2(dirty_total - 1); } /* -- 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