From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422863AbXCBEdK (ORCPT ); Thu, 1 Mar 2007 23:33:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422864AbXCBEdK (ORCPT ); Thu, 1 Mar 2007 23:33:10 -0500 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:43453 "EHLO netops-testserver-4.corp.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1422863AbXCBEdI (ORCPT ); Thu, 1 Mar 2007 23:33:08 -0500 Date: Thu, 1 Mar 2007 20:33:04 -0800 (PST) From: Christoph Lameter To: Andrew Morton cc: Nick Piggin , Mel Gorman , mingo@elte.hu, jschopp@austin.ibm.com, arjan@infradead.org, torvalds@linux-foundation.org, mbligh@mbligh.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: The performance and behaviour of the anti-fragmentation related patches In-Reply-To: <20070301202917.7abe4ad8.akpm@linux-foundation.org> Message-ID: References: <20070301101249.GA29351@skynet.ie> <20070301160915.6da876c5.akpm@linux-foundation.org> <20070302035751.GA15867@wotan.suse.de> <20070301202917.7abe4ad8.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 1 Mar 2007, Andrew Morton wrote: > Sorry, but this is crap. zones and nodes are distinct, physical concepts > and you're kidding yourself if you think you can somehow fudge things to make > one of them just go away. > > Think: ZONE_DMA32 on an Opteron machine. I don't think there is a sane way > in which we can fudge away the distinction between > bus-addresses-which-have-the-32-upper-bits-zero and > memory-which-is-local-to-each-socket. Of course you can. Add a virtual DMA and DMA32 zone/node and extract the relevant memory from the base zone/node.