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Date: Wed, 21 Mar 2007 07:35:04 -0700 (PDT)
From: Christoph Lameter <christoph@lameter.com>
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To: Eric Dumazet <dada1@cosmosbay.com>
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       Andrew Morton <akpm@linux-foundation.org>,
       linux kernel <linux-kernel@vger.kernel.org>
Subject: Re: [RFC] SLAB : NUMA cache_free_alien() very expensive because of
 virt_to_slab(objp); nodeid = slabp->nodeid;
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On Wed, 21 Mar 2007, Eric Dumazet wrote:

> If numa_node_id() is equal to the node of the page containing the first byte
> of the object, then object is on the local node. Or what ?

No. The slab (the page you are referring to) may have been allocated for 
another node and been tracked via the node structs of that other node. We 
were just falling back to the node that now appears to be local.