From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752569AbXCUMBx (ORCPT ); Wed, 21 Mar 2007 08:01:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752580AbXCUMBx (ORCPT ); Wed, 21 Mar 2007 08:01:53 -0400 Received: from mx1.redhat.com ([66.187.233.31]:56251 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752569AbXCUMBw (ORCPT ); Wed, 21 Mar 2007 08:01:52 -0400 Message-ID: <46011E8F.2000109@redhat.com> Date: Wed, 21 Mar 2007 08:01:19 -0400 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Thunderbird 1.5.0.7 (X11/20061008) MIME-Version: 1.0 To: Nikita Danilov CC: Linux Kernel Mailing List , linux-mm Subject: Re: [RFC][PATCH] split file and anonymous page queues #3 References: <46005B4A.6050307@redhat.com> <17920.61568.770999.626623@gargle.gargle.HOWL> <460115D9.7030806@redhat.com> <17921.7074.900919.784218@gargle.gargle.HOWL> In-Reply-To: <17921.7074.900919.784218@gargle.gargle.HOWL> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Nikita Danilov wrote: > Probably I am missing something, but I don't see how that can help. For > example, suppose (for simplicity) that we have swappiness of 100%, and > that fraction of referenced anon pages gets slightly less than of file > pages. get_scan_ratio() increases anon_percent, and shrink_zone() starts > scanning anon queue more aggressively. As a result, pages spend less > time there, and have less chance of ever being accessed, reducing > fraction of referenced anon pages further, and triggering further > increase in the amount of scanning, etc. Doesn't this introduce positive > feed-back loop? It's a possibility, but I don't think it will be much of an issue in practice. If it is, we can always use refaults as a correcting mechanism - which would have the added benefit of being able to do streaming IO without putting any pressure on the active list, essentially clock-pro replacement with just some tweaks to shrink_list()... -- Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic.