From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl@linux-foundation.org>
Subject: Re: [PATCH] percpu: add optimized generic percpu accessors
Date: Wed, 28 Jan 2009 11:45:28 -0500 (EST)
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References: <200901271213.18605.rusty@rustcorp.com.au> <497E705B.5000302@kernel.org> <alpine.DEB.1.10.0901271506580.3114@qirst.com> <20090127.134747.153565246.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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On Tue, 27 Jan 2009, David Miller wrote:

> > Why wont it scale? this is a separate TLB entry for each processor.
>
> The IA64 per-cpu TLB entry only covers 64k which makes use of it for
> dynamic per-cpu stuff out of the question.  That's why it "doesn't
> scale"

IA64 supports varying page sizes. You can use a 128k TLB entry etc.