Date: Wed, 28 Jan 2009 12:47:19 -0800 (PST)
Message-Id: <20090128.124719.200850704.davem@davemloft.net>
To: cl@linux-foundation.org
Cc: tj@kernel.org, rusty@rustcorp.com.au, mingo@elte.hu,
       herbert@gondor.apana.org.au, akpm@linux-foundation.org, hpa@zytor.com,
       brgerst@gmail.com, ebiederm@xmission.com, travis@sgi.com,
       linux-kernel@vger.kernel.org, steiner@sgi.com, hugh@veritas.com,
       netdev@vger.kernel.org, mathieu.desnoyers@polymtl.ca
Subject: Re: [PATCH] percpu: add optimized generic percpu accessors
From: David Miller <davem@davemloft.net>
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	<20090127.134747.153565246.davem@davemloft.net>
	<alpine.DEB.1.10.0901281145050.13825@qirst.com>
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From: Christoph Lameter <cl@linux-foundation.org>
Date: Wed, 28 Jan 2009 11:45:28 -0500 (EST)

> 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.

Good luck moving to a larger size dynamically at run time.

It really isn't a tenable solution.
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