From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arjan van de Ven <arjan@infradead.org>
Date: Thu, 23 Dec 2004 19:49:13 +0000
Subject: Re: Prezeroing V2 [0/3]: Why and When it works
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List-Id: <linux-ia64.vger.kernel.org>
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To: Christoph Lameter <clameter@sgi.com>
Cc: akpm@osdl.org, linux-ia64@vger.kernel.org, torvalds@osdl.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org


> The most expensive operation in the page fault handler is (apart of SMP
> locking overhead) the zeroing of the page. This zeroing means that all
> cachelines of the faulted page (on Altix that means all 128 cachelines of
> 128 byte each) must be loaded and later written back. This patch allows to
> avoid having to load all cachelines if only a part of the cachelines of
> that page is needed immediately after the fault.

eh why will all cachelines be loaded? Surely you can avoid the write-
allocate behavior for this case.....