Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263182AbUD2D5r (ORCPT ); Wed, 28 Apr 2004 23:57:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263174AbUD2D5m (ORCPT ); Wed, 28 Apr 2004 23:57:42 -0400 Received: from smtp101.mail.sc5.yahoo.com ([216.136.174.139]:37745 "HELO smtp101.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S263173AbUD2D5g (ORCPT ); Wed, 28 Apr 2004 23:57:36 -0400 Message-ID: <40907D23.7000103@yahoo.com.au> Date: Thu, 29 Apr 2004 13:57:23 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040401 Debian/1.6-4 X-Accept-Language: en MIME-Version: 1.0 To: Andrew Morton CC: Paul Mackerras , brettspamacct@fastclick.com, jgarzik@pobox.com, linux-kernel@vger.kernel.org Subject: Re: ~500 megs cached yet 2.6.5 goes into swap hell References: <409021D3.4060305@fastclick.com> <20040428170106.122fd94e.akpm@osdl.org> <409047E6.5000505@pobox.com> <40905127.3000001@fastclick.com> <20040428180038.73a38683.akpm@osdl.org> <16528.23219.17557.608276@cargo.ozlabs.ibm.com> <20040428185342.0f61ed48.akpm@osdl.org> In-Reply-To: <20040428185342.0f61ed48.akpm@osdl.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1673 Lines: 39 Andrew Morton wrote: > Paul Mackerras wrote: > >>Andrew Morton writes: >> >> >>>My point is that decreasing the tendency of the kernel to swap stuff out is >>>wrong. You really don't want hundreds of megabytes of BloatyApp's >>>untouched memory floating about in the machine. Get it out on the disk, >>>use the memory for something useful. >> >>What I have noticed with 2.6.6-rc1 on my dual G5 is that if I rsync a >>gigabyte or so of data over to another machine, it then takes several >>seconds to change focus from one window to another. I can see it >>slowly redraw the window title bars. It looks like the window manager >>is getting swapped/paged out. >> >>This machine has 2.5GB of ram, so I really don't see why it would need >>to swap at all. There should be plenty of page cache pages that are >>clean and not in use by any process that could be discarded. It seems >>like as soon as there is any memory shortage at all it picks on the >>window manager and chucks out all its pages. :( >> > > > I suspect rsync is taking two passes across the source files for its > checksumming thing. If so, this will defeat the pagecache use-once logic. > The kernel sees the second touch of the pages and assumes that there will > be a third touch. > I'm not very impressed with the pagecache use-once logic, and I have a patch to remove it completely and treat non-mapped touches (IMO) more sanely. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/