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Date: Sat, 08 Dec 2007 03:52:53 +0530
From: Balbir Singh <balbir@linux.vnet.ibm.com>
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To: Arnd Bergmann <arnd@arndb.de>
CC: linuxppc-dev@ozlabs.org, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Fake NUMA emulation for PowerPC
References: <20071207211425.10223.91240.sendpatchset@balbir-laptop> <200712072301.38723.arnd@arndb.de>
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Arnd Bergmann wrote:
> On Friday 07 December 2007, 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>
>>
>> node range is of the format <range1>,<range2>,...<rangeN>
> 
> Excellent idea! I'd love to have this in RHEL5u1, because that would make
> that distro boot on certain machines that have more memory than is supported
> without an iommu driver. The problem we have is that when you simply
> say mem=1G but all of the first gigabyte is on the first node, you end
> up with a memoryless node, which is not supported.
> 
> Unfortunately, it comes too late for me now, as all new distros already boot
> on Cell machines that need an IOMMU.

Very interesting use case! I am sure there are others were fake NUMA
nodes can be applied. I just listed one other in another email, apart
from using it for playing around with NUMA like machines.

-- 
	Warm Regards,
	Balbir Singh
	Linux Technology Center
	IBM, ISTL
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