From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e1.ny.us.ibm.com (e1.ny.us.ibm.com [32.97.182.141]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e1.ny.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTP id BD9ACDDE23 for ; Sat, 8 Dec 2007 09:26:41 +1100 (EST) Received: from d01relay04.pok.ibm.com (d01relay04.pok.ibm.com [9.56.227.236]) by e1.ny.us.ibm.com (8.13.8/8.13.8) with ESMTP id lB7MQcNw016184 for ; Fri, 7 Dec 2007 17:26:38 -0500 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id lB7MQbIg137106 for ; Fri, 7 Dec 2007 17:26:37 -0500 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id lB7MQbAa014890 for ; Fri, 7 Dec 2007 17:26:37 -0500 Message-ID: <4759C89B.9000709@linux.vnet.ibm.com> Date: Sat, 08 Dec 2007 03:56:35 +0530 From: Balbir Singh MIME-Version: 1.0 To: Nathan Lynch Subject: Re: [PATCH] Fake NUMA emulation for PowerPC References: <20071207211425.10223.91240.sendpatchset@balbir-laptop> <20071207221106.GH16824@localdomain> In-Reply-To: <20071207221106.GH16824@localdomain> Content-Type: text/plain; charset=ISO-8859-1 Cc: linuxppc-dev@ozlabs.org, LKML Reply-To: balbir@linux.vnet.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Nathan Lynch wrote: > Hi Balbir- > > Balbir Singh wrote: >> >> Here's a dumb simple implementation of fake NUMA nodes for PowerPC. Fake >> NUMA nodes can be specified using the following command line option >> >> numa=fake= >> >> node range is of the format ,,... >> >> Each of the rangeX parameters is passed using memparse(). I find the patch >> useful for fake NUMA emulation on my simple PowerPC machine. I've tested it >> on a non-numa box with the following arguments >> >> numa=fake=1G >> numa=fake=1G,2G >> name=fake=1G,512M,2G >> numa=fake=1500M,2800M mem=3500M >> numa=fake=1G mem=512M >> numa=fake=1G mem=1G > > So this doesn't appear to allow one to assign cpus to fake nodes? Do > all cpus just get assigned to node 0 with numa=fake? > Yes, they all appear on node 0. We could have tweaks to distribute CPU's as well. > A different approach that occurs to me is to use kexec with a doctored > device tree (i.e. with the ibm,associativity properties modified to > reflect your desired topology). Perhaps a little bit obscure, but it > seems more flexible. > That would be interesting, but it always means that we need to run kexec, which might involve two boots. -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL