From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758222AbYFIC62 (ORCPT ); Sun, 8 Jun 2008 22:58:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756242AbYFIC6U (ORCPT ); Sun, 8 Jun 2008 22:58:20 -0400 Received: from mx1.redhat.com ([66.187.233.31]:43437 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756197AbYFIC6U (ORCPT ); Sun, 8 Jun 2008 22:58:20 -0400 Date: Sun, 8 Jun 2008 22:58:00 -0400 From: Rik van Riel To: Andrew Morton Cc: linux-kernel@vger.kernel.org, lee.schermerhorn@hp.com, kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org, eric.whitney@hp.com Subject: Re: [PATCH -mm 13/25] Noreclaim LRU Infrastructure Message-ID: <20080608225800.17d2e29b@bree.surriel.com> In-Reply-To: <20080608165434.67c87e5c.akpm@linux-foundation.org> References: <20080606202838.390050172@redhat.com> <20080606202859.291472052@redhat.com> <20080606180506.081f686a.akpm@linux-foundation.org> <20080608163413.08d46427@bree.surriel.com> <20080608135704.a4b0dbe1.akpm@linux-foundation.org> <20080608173244.0ac4ad9b@bree.surriel.com> <20080608162208.a2683a6c.akpm@linux-foundation.org> <20080608193420.2a9cc030@bree.surriel.com> <20080608165434.67c87e5c.akpm@linux-foundation.org> Organization: Red Hat, Inc. X-Mailer: Claws Mail 3.0.2 (GTK+ 2.10.4; x86_64-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 List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 8 Jun 2008 16:54:34 -0700 Andrew Morton wrote: > ho hum. Can you remind us what problems this patchset actually > addresses? Preferably in order of seriousness? Here are some other problems that my patch series can easily fix, because file cache and anon/swap backed pages live on separate LRUs: http://feedblog.org/2007/09/29/using-o_direct-on-linux-and-innodb-to-fix-swap-insanity/ http://blogs.smugmug.com/don/2008/05/01/mysql-and-the-linux-swap-problem/ I do not know for sure whether the patch set does fix it yet for everyone, or whether it needs some more tuning first, but it is fairly easily fixable by tweaking the relative pressure on both sets of LRU lists. No tricks of skipping over one type of pages while scanning, or treating the referenced bits differently when the moon is in some particular phase required - one set of lists for each type of pages, and variable pressure between the two. -- All rights reversed.