From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH 2/3] add dev_to_node() From: Lee Schermerhorn In-Reply-To: References: <20061030141501.GC7164@lst.de> <20061030.143357.130208425.davem@davemloft.net> <20061104225629.GA31437@lst.de> <20061108114038.59831f9d.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain Date: Fri, 10 Nov 2006 13:28:25 -0500 Message-Id: <1163183306.15159.6.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: KAMEZAWA Hiroyuki , Christoph Hellwig , davem@davemloft.net, linux-kernel@vger.kernel.org, netdev@oss.sgi.com, linux-mm@kvack.org List-ID: On Fri, 2006-11-10 at 10:16 -0800, Christoph Lameter wrote: > On Wed, 8 Nov 2006, KAMEZAWA Hiroyuki wrote: > > > I wonder there are no code for creating NODE_DATA() for device-only-node. > > On IA64 we remap nodes with no memory / cpus to the nearest node with > memory. I think that is sufficient. I don't think this happens anymore. Back in the ~2.6.5 days, when we would configure our numa platforms with 100% of memory interleaved [in hardware at cache line granularity], the cpus would move to the interleaved "pseudo-node" and the memoryless nodes would be removed. numactl --hardware would show something like this: # uname -r 2.6.5-7.244-default # numactl --hardware available: 1 nodes (0-0) node 0 size: 65443 MB node 0 free: 64506 MB I started seeing different behavior about the time SPARSEMEM went in. Now, with a 2.6.16 base kernel [same platform, hardware interleaved memory], I see: # uname -r# numactl --hardware available: 5 nodes (0-4) node 0 size: 0 MB node 0 free: 0 MB node 1 size: 0 MB node 1 free: 0 MB node 2 size: 0 MB node 2 free: 0 MB node 3 size: 0 MB node 3 free: 0 MB node 4 size: 65439 MB node 4 free: 64492 MB node distances: node 0 1 2 3 4 0: 10 17 17 17 14 1: 17 10 17 17 14 2: 17 17 10 17 14 3: 17 17 17 10 14 4: 14 14 14 14 10 2.6.16.21-0.8-default [Aside: The firmware/SLIT says that the interleaved memory is closer to all nodes that other nodes' memory. This has interesting implications for the "overflow" zone lists...] Lee -- 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