Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758510AbYFJTRd (ORCPT ); Tue, 10 Jun 2008 15:17:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754172AbYFJTRZ (ORCPT ); Tue, 10 Jun 2008 15:17:25 -0400 Received: from relay1.sgi.com ([192.48.171.29]:49984 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753970AbYFJTRY (ORCPT ); Tue, 10 Jun 2008 15:17:24 -0400 Date: Tue, 10 Jun 2008 12:17:23 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Andrew Morton cc: Rik van Riel , 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 In-Reply-To: <20080608165434.67c87e5c.akpm@linux-foundation.org> Message-ID: 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> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1214 Lines: 29 On Sun, 8 Jun 2008, Andrew Morton wrote: > And it will take longer to get those problems sorted out if 32-bt > machines aren't even compiing the new code in. The problem is going to be less if we dependedn on CONFIG_PAGEFLAGS_EXTENDED instead of 64 bit. This means that only certain 32bit NUMA/sparsemem configs cannot do this due to lack of page flags. I did the pageflags rework in part because of Rik's project. > ho hum. Can you remind us what problems this patchset actually > addresses? Preferably in order of seriousness? (The [0/n] description > told us about the implementation but forgot to tell us anything about > what it was fixing). Because I guess we should have a think about > alternative approaches. It solves the livelock while reclaiming issues that we see more and more. There are loads that have lots of unreclaimable pages. These are frequently and uselessly scanned under memory pressure. The larger the memory the more problems. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/