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Date: Tue, 18 Feb 2014 15:49:22 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
To: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Subject: Re: [RFC PATCH 2/3] topology: support node_numa_mem() for determining
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On Tue, 18 Feb 2014, Nishanth Aravamudan wrote:

> We use the topology provided by the hypervisor, it does actually reflect
> where CPUs and memory are, and their corresponding performance/NUMA
> characteristics.

And so there are actually nodes without memory that have processors?
Can the hypervisor or the linux arch code be convinced to ignore nodes
without memory or assign a sane default node to processors?

> > Ok then also move the memory of the local node somewhere?
>
> This happens below the OS, we don't control the hypervisor's decisions.
> I'm not sure if that's what you are suggesting.

You could also do this from the powerpc arch code by sanitizing the
processor / node information that is then used by Linux.