From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751896Ab1HLNI5 (ORCPT ); Fri, 12 Aug 2011 09:08:57 -0400 Received: from merlin.infradead.org ([205.233.59.134]:54383 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751196Ab1HLNI4 convert rfc822-to-8bit (ORCPT ); Fri, 12 Aug 2011 09:08:56 -0400 Subject: Re: [PATCH 2/5] writeback: dirty position control From: Peter Zijlstra To: Wu Fengguang Cc: "linux-fsdevel@vger.kernel.org" , Andrew Morton , Jan Kara , Christoph Hellwig , Dave Chinner , Greg Thelen , Minchan Kim , Vivek Goyal , Andrea Righi , linux-mm , LKML Date: Fri, 12 Aug 2011 15:08:24 +0200 In-Reply-To: <20110812125952.GA16675@localhost> References: <20110806084447.388624428@intel.com> <20110806094526.733282037@intel.com> <1312811193.10488.33.camel@twins> <20110808141128.GA22080@localhost> <1312814501.10488.41.camel@twins> <20110808230535.GC7176@localhost> <1313153657.6576.40.camel@twins> <20110812125952.GA16675@localhost> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Mailer: Evolution 3.0.2- Message-ID: <1313154504.6576.44.camel@twins> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2011-08-12 at 20:59 +0800, Wu Fengguang wrote: > On Fri, Aug 12, 2011 at 08:54:17PM +0800, Peter Zijlstra wrote: > > On Fri, 2011-08-12 at 00:56 +0200, Peter Zijlstra wrote: > > > > > > s - x 3 > > > f(x) := 1 + (-----) > > > d > > > > > btw, if you want steeper slopes for rampup and brake you can add another > > factor like: > > > > s - x 3 > > f(x) := 1 + a(-----) > > d > > > > And solve the whole f(l)=0 thing again to determine d in l and a. > > > > For 0 < a < 1 the slopes increase. > > Yes, we can leave it as a future tuning option. For now I'm pretty > satisfied with the current function's shape :) Oh for sure, it just occurred to me when looking at your plots and thought I'd at least mention it.. You know something to poke at on a rainy afternoon ;-) From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH 2/5] writeback: dirty position control Date: Fri, 12 Aug 2011 15:08:24 +0200 Message-ID: <1313154504.6576.44.camel@twins> References: <20110806084447.388624428@intel.com> <20110806094526.733282037@intel.com> <1312811193.10488.33.camel@twins> <20110808141128.GA22080@localhost> <1312814501.10488.41.camel@twins> <20110808230535.GC7176@localhost> <1313153657.6576.40.camel@twins> <20110812125952.GA16675@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Cc: "linux-fsdevel@vger.kernel.org" , Andrew Morton , Jan Kara , Christoph Hellwig , Dave Chinner , Greg Thelen , Minchan Kim , Vivek Goyal , Andrea Righi , linux-mm , LKML To: Wu Fengguang Return-path: In-Reply-To: <20110812125952.GA16675@localhost> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Fri, 2011-08-12 at 20:59 +0800, Wu Fengguang wrote: > On Fri, Aug 12, 2011 at 08:54:17PM +0800, Peter Zijlstra wrote: > > On Fri, 2011-08-12 at 00:56 +0200, Peter Zijlstra wrote: > > >=20 > > > s - x 3 > > > f(x) :=3D 1 + (-----) > > > d > > >=20 > > btw, if you want steeper slopes for rampup and brake you can add anothe= r > > factor like: > >=20 > > s - x 3 > > f(x) :=3D 1 + a(-----) > > d > > =20 > > And solve the whole f(l)=3D0 thing again to determine d in l and a. > >=20 > > For 0 < a < 1 the slopes increase. >=20 > Yes, we can leave it as a future tuning option. For now I'm pretty > satisfied with the current function's shape :) Oh for sure, it just occurred to me when looking at your plots and thought I'd at least mention it.. You know something to poke at on a rainy afternoon ;-) -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta8.messagelabs.com (mail6.bemta8.messagelabs.com [216.82.243.55]) by kanga.kvack.org (Postfix) with ESMTP id D50F1900138 for ; Fri, 12 Aug 2011 09:08:49 -0400 (EDT) Subject: Re: [PATCH 2/5] writeback: dirty position control From: Peter Zijlstra Date: Fri, 12 Aug 2011 15:08:24 +0200 In-Reply-To: <20110812125952.GA16675@localhost> References: <20110806084447.388624428@intel.com> <20110806094526.733282037@intel.com> <1312811193.10488.33.camel@twins> <20110808141128.GA22080@localhost> <1312814501.10488.41.camel@twins> <20110808230535.GC7176@localhost> <1313153657.6576.40.camel@twins> <20110812125952.GA16675@localhost> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Message-ID: <1313154504.6576.44.camel@twins> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Wu Fengguang Cc: "linux-fsdevel@vger.kernel.org" , Andrew Morton , Jan Kara , Christoph Hellwig , Dave Chinner , Greg Thelen , Minchan Kim , Vivek Goyal , Andrea Righi , linux-mm , LKML On Fri, 2011-08-12 at 20:59 +0800, Wu Fengguang wrote: > On Fri, Aug 12, 2011 at 08:54:17PM +0800, Peter Zijlstra wrote: > > On Fri, 2011-08-12 at 00:56 +0200, Peter Zijlstra wrote: > > >=20 > > > s - x 3 > > > f(x) :=3D 1 + (-----) > > > d > > >=20 > > btw, if you want steeper slopes for rampup and brake you can add anothe= r > > factor like: > >=20 > > s - x 3 > > f(x) :=3D 1 + a(-----) > > d > > =20 > > And solve the whole f(l)=3D0 thing again to determine d in l and a. > >=20 > > For 0 < a < 1 the slopes increase. >=20 > Yes, we can leave it as a future tuning option. For now I'm pretty > satisfied with the current function's shape :) Oh for sure, it just occurred to me when looking at your plots and thought I'd at least mention it.. You know something to poke at on a rainy afternoon ;-) -- 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