From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id 532CF6B0071 for ; Wed, 24 Nov 2010 07:46:50 -0500 (EST) Subject: Re: [PATCH 08/13] writeback: quit throttling when bdi dirty pages dropped low From: Peter Zijlstra In-Reply-To: <20101124123023.GA10413@localhost> References: <20101117042720.033773013@intel.com> <20101117042850.245782303@intel.com> <1290597233.2072.454.camel@laptop> <20101124123023.GA10413@localhost> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Date: Wed, 24 Nov 2010 13:46:51 +0100 Message-ID: <1290602811.2072.462.camel@laptop> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Andrew Morton , Jan Kara , Christoph Hellwig , Dave Chinner , Theodore Ts'o , Chris Mason , Mel Gorman , Rik van Riel , KOSAKI Motohiro , linux-mm , "linux-fsdevel@vger.kernel.org" , LKML List-ID: On Wed, 2010-11-24 at 20:30 +0800, Wu Fengguang wrote: >=20 > For the 1-dd case, it looks better to lower the break threshold to > 125ms. After all, it's not easy for the dirty pages to drop by 250ms > worth of data when you only slept 200ms (note: the max pause time has > been doubled mainly for servers). >=20 > - if (nr_dirty < dirty_thresh && > - bdi_prev_dirty - bdi_dirty > (long)bdi->write_bandwid= th / 4) > + if (nr_dirty <=3D dirty_thresh && > + bdi_prev_dirty - bdi_dirty > (long)bdi->write_bandwid= th / 8) > break; Hrm, but 125ms worth in 200ms is rather easy, you'd want to keep that limit above what the pause should give you, right? -- 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 policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org