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Date: Wed, 07 Sep 2005 07:28:44 -0700
From: "Martin J. Bligh" <mbligh@mbligh.org>
Reply-To: "Martin J. Bligh" <mbligh@mbligh.org>
To: Christoph Lameter <clameter@engr.sgi.com>, torvalds@osdl.org
Cc: akpm@osdl.org, nickpiggin@yahoo.com.au, hugh@veritas.com,
       linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: Hugh's alternate page fault scalability approach on 512p Altix
Message-ID: <20660000.1126103324@[10.10.2.4]>
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> Anticipatory prefaulting raises the highest fault rate obtainable three-fold
> through gang scheduling faults but may allocate some pages to a task that are
> not needed.

IIRC that costed more than it saved, at least for forky workloads like a
kernel compile - extra cost in zap_pte_range etc. If things have changed
substantially in that path, I guess we could run the numbers again - has
been a couple of years.

M.