From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@osdl.org>
Date: Wed, 12 Jan 2005 23:30:33 +0000
Subject: Re: page table lock patch V15 [0/7]: overview
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To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: clameter@sgi.com, torvalds@osdl.org, ak@muc.de, hugh@veritas.com, linux-mm@kvack.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org

Nick Piggin <nickpiggin@yahoo.com.au> wrote:
>
> So my patches cost about 7% in lmbench fork benchmark.

OK, well that's the sort of thing we need to understand fully.  What sort
of CPU was that on?

Look, -7% on a 2-way versus +700% on a many-way might well be a tradeoff we
agree to take.  But we need to fully understand all the costs and benefits.