From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: RFT: updatedb "morning after" problem [was: Re: -mm merge plans for 2.6.23] From: Mike Galbraith In-Reply-To: <20070727030040.0ea97ff7.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> <20070727030040.0ea97ff7.akpm@linux-foundation.org> Content-Type: text/plain Date: Fri, 27 Jul 2007 12:25:18 +0200 Message-Id: <1185531918.8799.17.camel@Homer.simpson.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: 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, 2007-07-27 at 03:00 -0700, Andrew Morton wrote: > 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. The balance in _my_ world seems just fine. I don't let any of those system maintenance things run while I'm using the system, and it doesn't bother me if my working set has to be reconstructed after heavy-weight maintenance things are allowed to run. I'm not seeing anything I wouldn't expect to see when running a job the size of updatedb. -Mike -- 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