From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 11 Jun 2008 15:29:22 +0900 From: Paul Mundt Subject: Re: [PATCH -mm 13/25] Noreclaim LRU Infrastructure Message-ID: <20080611062922.GA30983@linux-sh.org> References: <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> <20080610153702.4019e042@cuia.bos.redhat.com> <20080610143334.c53d7d8a.akpm@linux-foundation.org> <20080611050914.GA27488@linux-sh.org> <20080610231642.6b4b5a53.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080610231642.6b4b5a53.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Rik van Riel , clameter@sgi.com, linux-kernel@vger.kernel.org, lee.schermerhorn@hp.com, kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org, eric.whitney@hp.com, Andi Kleen , Ingo Molnar , Andy Whitcroft List-ID: On Tue, Jun 10, 2008 at 11:16:42PM -0700, Andrew Morton wrote: > On Wed, 11 Jun 2008 14:09:15 +0900 Paul Mundt wrote: > > On Tue, Jun 10, 2008 at 02:33:34PM -0700, Andrew Morton wrote: > > > Maybe it's time to bite the bullet and kill i386 NUMA support. afaik > > > it's just NUMAQ and a 2-node NUMAish machine which IBM made (as400?) > > > > > > arch/sh uses NUMA for 32-bit, I believe. But I don't know what its > > > maximum node count is. The default for sh NODES_SHIFT is 3. > > > > In terms of memory nodes, systems vary from 2 up to 16 or so. It gets > > gradually more complex in the SMP cases where we are 3-4 levels deep in > > various types of memories that we expose as nodes (ie, 4-8 CPUs with a > > dozen different memories or so at various interconnect levels). > > Thanks. > > Andi has suggested that we can remove the node-ID encoding from > page.flags on x86 because that info is available elsewhere, although a > bit more slowly. > > > > There wouldn't be much point in doing that unless we did it for all > 32-bit architectures. How much trouble would it cause sh? > At first glance I don't think that should be too bad. We only do NUMA through sparsemem anyways, and we have pretty much no overlap in any of the ranges, so simply setting NODE_NOT_IN_PAGE_FLAGS should be ok there. Given the relatively small number of pages we have, the added cost of page_to_nid() referencing section_to_node_table should still be tolerable. I'll give it a go and see what the numbers look like. > > As far as testing goes, it's part of the regular build and regression > > testing for a number of boards, which we verify on a daily basis > > (although admittedly -mm gets far less testing, even though that's where > > most of the churn in this area tends to be). > > Oh well, that's what -rc is for :( > > It would be good if someone over there could start testing linux-next. > Once I get my act together that will include most-of-mm anyway. > Agreed. This is something we're attempting to add in to our automated testing at present. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org