From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760203Ab2D0Nzz (ORCPT ); Fri, 27 Apr 2012 09:55:55 -0400 Received: from mx1.redhat.com ([209.132.183.28]:62135 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758058Ab2D0Nzy (ORCPT ); Fri, 27 Apr 2012 09:55:54 -0400 Message-ID: <4F9AA54E.6050007@redhat.com> Date: Fri, 27 Apr 2012 09:55:26 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:11.0) Gecko/20120329 Thunderbird/11.0.1 MIME-Version: 1.0 To: Christoph Lameter CC: Richard Davies , Satoru Moriya , KOSAKI Motohiro , Jerome Marchand , KOSAKI Motohiro , "jweiner@redhat.com" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "lwoodman@redhat.com" , "shaohua.li@intel.com" , "dle-develop@lists.sourceforge.net" , Seiji Aguchi , Minchan Kim Subject: Re: [RFC][PATCH] avoid swapping out with swappiness==0 References: <20120424082019.GA18395@alpha.arachsys.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/26/2012 10:50 AM, Christoph Lameter wrote: > On Tue, 24 Apr 2012, Richard Davies wrote: > >> I strongly believe that Linux should have a way to turn off swapping unless >> absolutely necessary. This means that users like us can run with swap >> present for emergency use, rather than having to disable it because of the >> side effects. > > Agree. And this ooperation mode should be the default behavior given that > swapping is a very slow and tedious process these days. I believe that is a bad idea. With cgroups, the situation is a whole lot less obvious than with the simple test done in this patch. Lets see how the 3.4 code behaves, and if we need any additional changes to reduce swapping and step up reclaiming of page cache... -- All rights reversed