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Date: Tue, 11 Feb 2014 12:45:28 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
To: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Subject: Re: [RFC PATCH 2/3] topology: support node_numa_mem() for determining
 the fallback node
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Cc: Han Pingtian <hanpt@linux.vnet.ibm.com>,
 Nishanth Aravamudan <nacc@linux.vnet.ibm.com>, Matt Mackall <mpm@selenic.com>,
 Pekka Enberg <penberg@kernel.org>,
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On Mon, 10 Feb 2014, Joonsoo Kim wrote:

> On Fri, Feb 07, 2014 at 12:51:07PM -0600, Christoph Lameter wrote:
> > Here is a draft of a patch to make this work with memoryless nodes.
> >
> > The first thing is that we modify node_match to also match if we hit an
> > empty node. In that case we simply take the current slab if its there.
>
> Why not inspecting whether we can get the page on the best node such as
> numa_mem_id() node?

Its expensive to do so.

> empty_node cannot be set on memoryless node, since page allocation would
> succeed on different node.

Ok then we need to add a check for being on the rignt node there too.