From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750982AbWFUETS (ORCPT ); Wed, 21 Jun 2006 00:19:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751979AbWFUETR (ORCPT ); Wed, 21 Jun 2006 00:19:17 -0400 Received: from smtp.osdl.org ([65.172.181.4]:41158 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1750982AbWFUETR (ORCPT ); Wed, 21 Jun 2006 00:19:17 -0400 Date: Tue, 20 Jun 2006 21:19:05 -0700 From: Andrew Morton To: Mark Lord Cc: js@linuxtv.org, pavel@ucw.cz, p.lundkvist@telia.com, linux-kernel@vger.kernel.org, rjw@sisk.pl Subject: Re: [PATCH] Page writeback broken after resume: wb_timer lost Message-Id: <20060620211905.c7307b9f.akpm@osdl.org> In-Reply-To: <4498C6CF.3080206@rtr.ca> References: <20060520130326.GA6092@localhost> <20060520103728.6f3b3798.akpm@osdl.org> <20060520225018.GC8490@elf.ucw.cz> <20060520171244.4399bc54.akpm@osdl.org> <20060616212410.GA6821@linuxtv.org> <4496C5AC.3030809@rtr.ca> <4498BF51.5090204@rtr.ca> <20060620205415.d808ace9.akpm@osdl.org> <4498C6CF.3080206@rtr.ca> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.17; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 21 Jun 2006 00:10:55 -0400 Mark Lord wrote: > Andrew Morton wrote: > > On Tue, 20 Jun 2006 23:38:57 -0400 > > Mark Lord wrote: > > > >>> I just gave it a try here. With or without a suspend/resume cycle after > >>> boot, > >>> the "sync" time is much quicker. But the Dirty count in /proc/meminfo > >>> still shows very huge (eg. 600MB) values that never really get smaller > >>> until I type "sync". But that subsequent "sync" only takes a couple > >>> of seconds now, rather than 10-20 seconds like before. > >> .. > >> > >> Yup, behaviour is *definitely* much better now. I'm not sure why > >> the /proc/meminfo "Dirty" count lags behind reality, but the disk > >> is being kept much more up-to-date than without this patch. > > > > Are you able to come up with a foolproof set of steps which would allow the > > laggy-dirtiness to be reproduced by yours truly? > > Heh.. don't I wish! > > The best is still as described originally: > > http://lkml.org/lkml/2006/2/6/170 > > Basically, "cat" a ton of huge files together into a single new one, > and then watch /proc/meminfo to see what happens. For me, the count > there still just hangs at some big number like 500MB until I type "sync", > at which point it (nearly) instantly now goes to zero. > > Previous to this patch, the "sync" actually resulted in a ton of disk writes, > but now those happen on the tail end of the "cat" command, as they should. > > My kernel .config is available from http://rtr.ca/dell_i9300/kernel/latest/ Is that after a suspend/resume, or does it happen after a reboot? Are you sure all the dirty memory doesn't get autocleaned after 30-60 seconds?