From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261233AbULTID0 (ORCPT ); Mon, 20 Dec 2004 03:03:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261175AbULTICX (ORCPT ); Mon, 20 Dec 2004 03:02:23 -0500 Received: from fw.osdl.org ([65.172.181.6]:10373 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S261492AbULTHJK (ORCPT ); Mon, 20 Dec 2004 02:09:10 -0500 Date: Sun, 19 Dec 2004 23:07:54 -0800 From: Andrew Morton To: Nick Piggin Cc: riel@redhat.com, kernel@kolivas.org, mr@ramendik.ru, akpm@digeo.com, lista4@comhem.se, linux-kernel@vger.kernel.org Subject: Re: 2.6.10-rc3: kswapd eats CPU on start of memory-eating task Message-Id: <20041219230754.64c0e52e.akpm@osdl.org> In-Reply-To: <1103517225.5093.12.camel@npiggin-nld.site> References: <14514245.1103496059334.JavaMail.tomcat@pne-ps4-sn2> <41C6073B.6030204@yahoo.com.au> <20041219155722.01b1bec0.akpm@digeo.com> <200412200303.35807.mr@ramendik.ru> <41C640DE.7050002@kolivas.org> <1103517225.5093.12.camel@npiggin-nld.site> X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i386-redhat-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 Nick Piggin wrote: > > On Sun, 2004-12-19 at 22:21 -0500, Rik van Riel wrote: > > On Mon, 20 Dec 2004, Con Kolivas wrote: > > > > > I still suspect the thrash token patch even with the swap token timeout > > > at 0. Is it completely disabled at 0 or does it still do something? > > > > It makes it harder to page out pages from the task holding the > > token. I wonder if kswapd should try to steal the token away > > from the task holding it, so in effect nobody holds the token > > when the system isn't under a heavy swapping load. > > > > In that case, the first thing we need to do is disable thrash token > completely, and retest that. We still don't know for sure that it is > the problem. > > I don't have the code in front of me at the moment, but I'll be able > to send a patch to do that in a couple of hours, if nobody beats me > to it. This should disable the thrashing control code? --- 25/mm/rmap.c~a 2004-12-19 23:05:58.759420936 -0800 +++ 25-akpm/mm/rmap.c 2004-12-19 23:06:43.105679280 -0800 @@ -395,6 +395,8 @@ int page_referenced(struct page *page, i { int referenced = 0; + ignore_token = 1; + if (page_test_and_clear_young(page)) referenced++; _