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Date: Mon, 5 May 2008 12:12:56 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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       Jack Steiner <steiner@sgi.com>, Paul Jackson <pj@sgi.com>,
       Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: Hotplug CPU support for Oprofile
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The allocpercpu approach creates a pointer array and results in objects 
distributed over all of memory. A cpu alloc approach would place 
dynamically allocated per cpu objects together which is better for memory 
consumption (no need to align) and performance (same TLB entry, neigboring 
memory cells, possible shared cachelines).