From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261590AbULTRtT (ORCPT ); Mon, 20 Dec 2004 12:49:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261591AbULTRtS (ORCPT ); Mon, 20 Dec 2004 12:49:18 -0500 Received: from mail6.hitachi.co.jp ([133.145.228.41]:45040 "EHLO mail6.hitachi.co.jp") by vger.kernel.org with ESMTP id S261590AbULTRtO (ORCPT ); Mon, 20 Dec 2004 12:49:14 -0500 Message-ID: <41C710BB.9000705@sdl.hitachi.co.jp> Date: Tue, 21 Dec 2004 02:49:47 +0900 From: Hideo AOKI Organization: Systems Development Lab., Hitachi, Ltd. User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; ja-JP; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: ja MIME-Version: 1.0 To: Nick Piggin CC: Andrew Morton , lista4@comhem.se, linux-kernel@vger.kernel.org, mr@ramendik.ru, kernel@kolivas.org, riel@redhat.com Subject: Re: 2.6.10-rc3: kswapd eats CPU on start of memory-eating task References: <1329986.1103525472726.JavaMail.tomcat@pne-ps1-sn1> <20041219231250.457deb12.akpm@osdl.org> <41C682F1.20200@yahoo.com.au> In-Reply-To: <41C682F1.20200@yahoo.com.au> 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: > Andrew Morton wrote: [snip] >> Did anyone come up with a simple step-by-step procedure for >> reproducing the >> problem? It would be good if someone could do this, because I don't >> think >> we understand the root cause yet? > > I admit to generally being in the same boat as you with respect to > running complex userspace apps. > > However, based on this and other scattered reports, I'd say it seems > quite likely that token based thrashing control is the culprit. Based > on the cost/benefit, I wonder if we should disable TBTC by default for > 2.6.10, rather than trying to fix it, and try again for 2.6.11? Hello, I imagine that the issue might occur when only one process holds almost all memory and has swap token too long time. However, TBTC has a good effect in my workload. So, I think that it is better to keep VM tunable using TBTC. It may be a good idea to set 0 to default swap_token_timeout until we find the root cause. Best regards, Hideo AOKI