From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937163AbXG0KBd (ORCPT ); Fri, 27 Jul 2007 06:01:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762347AbXG0KBZ (ORCPT ); Fri, 27 Jul 2007 06:01:25 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:54920 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758032AbXG0KBY (ORCPT ); Fri, 27 Jul 2007 06:01:24 -0400 Date: Fri, 27 Jul 2007 03:00:40 -0700 From: Andrew Morton To: Mike Galbraith , Ingo Molnar , Frank Kingswood , Andi Kleen , Nick Piggin , Ray Lee , Jesper Juhl , ck list , Paul Jackson , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: RFT: updatedb "morning after" problem [was: Re: -mm merge plans for 2.6.23] Message-Id: <20070727030040.0ea97ff7.akpm@linux-foundation.org> In-Reply-To: <20070727014749.85370e77.akpm@linux-foundation.org> References: <9a8748490707231608h453eefffx68b9c391897aba70@mail.gmail.com> <46A57068.3070701@yahoo.com.au> <2c0942db0707232153j3670ef31kae3907dff1a24cb7@mail.gmail.com> <46A58B49.3050508@yahoo.com.au> <2c0942db0707240915h56e007e3l9110e24a065f2e73@mail.gmail.com> <46A6CC56.6040307@yahoo.com.au> <46A85D95.509@kingswood-consulting.co.uk> <20070726092025.GA9157@elte.hu> <20070726023401.f6a2fbdf.akpm@linux-foundation.org> <20070726094024.GA15583@elte.hu> <20070726030902.02f5eab0.akpm@linux-foundation.org> <1185454019.6449.12.camel@Homer.simpson.net> <20070726110549.da3a7a0d.akpm@linux-foundation.org> <1185513177.6295.21.camel@Homer.simpson.net> <1185521021.6295.50.camel@Homer.simpson.net> <20070727014749.85370e77.akpm@linux-foundation.org> X-Mailer: Sylpheed 2.4.1 (GTK+ 2.8.17; x86_64-unknown-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 Fri, 27 Jul 2007 01:47:49 -0700 Andrew Morton wrote: > More sophisticated testing is needed - there's something in > ext3-tools which will mmap, page in and hold a file for you. So much for that theory. afaict mmapped, active pagecache is immune to updatedb activity. It just sits there while updatedb continues munching away at the slab and blockdev pagecache which it instantiated. I assume we're never getting the VM into enough trouble to tip it over the start-reclaiming-mapped-pages threshold (ie: /proc/sys/vm/swappiness). Start the updatedb on this 128MB machine with 80MB of mapped pagecache, it falls to 55MB fairly soon and then never changes. So hrm. Are we sure that updatedb is the problem? There are quite a few heavyweight things which happen in the wee small hours. From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 27 Jul 2007 03:00:40 -0700 From: Andrew Morton Subject: Re: RFT: updatedb "morning after" problem [was: Re: -mm merge plans for 2.6.23] Message-Id: <20070727030040.0ea97ff7.akpm@linux-foundation.org> In-Reply-To: <20070727014749.85370e77.akpm@linux-foundation.org> References: <9a8748490707231608h453eefffx68b9c391897aba70@mail.gmail.com> <46A57068.3070701@yahoo.com.au> <2c0942db0707232153j3670ef31kae3907dff1a24cb7@mail.gmail.com> <46A58B49.3050508@yahoo.com.au> <2c0942db0707240915h56e007e3l9110e24a065f2e73@mail.gmail.com> <46A6CC56.6040307@yahoo.com.au> <46A85D95.509@kingswood-consulting.co.uk> <20070726092025.GA9157@elte.hu> <20070726023401.f6a2fbdf.akpm@linux-foundation.org> <20070726094024.GA15583@elte.hu> <20070726030902.02f5eab0.akpm@linux-foundation.org> <1185454019.6449.12.camel@Homer.simpson.net> <20070726110549.da3a7a0d.akpm@linux-foundation.org> <1185513177.6295.21.camel@Homer.simpson.net> <1185521021.6295.50.camel@Homer.simpson.net> <20070727014749.85370e77.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Mike Galbraith , Ingo Molnar , Frank Kingswood , Andi Kleen , Nick Piggin , Ray Lee , Jesper Juhl , ck list , Paul Jackson , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Fri, 27 Jul 2007 01:47:49 -0700 Andrew Morton wrote: > More sophisticated testing is needed - there's something in > ext3-tools which will mmap, page in and hold a file for you. So much for that theory. afaict mmapped, active pagecache is immune to updatedb activity. It just sits there while updatedb continues munching away at the slab and blockdev pagecache which it instantiated. I assume we're never getting the VM into enough trouble to tip it over the start-reclaiming-mapped-pages threshold (ie: /proc/sys/vm/swappiness). Start the updatedb on this 128MB machine with 80MB of mapped pagecache, it falls to 55MB fairly soon and then never changes. So hrm. Are we sure that updatedb is the problem? There are quite a few heavyweight things which happen in the wee small hours. -- 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/ . Don't email: email@kvack.org