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Date: Wed, 8 Dec 2004 09:57:09 -0800 (PST)
From: Christoph Lameter <clameter@sgi.com>
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To: "Luck, Tony" <tony.luck@intel.com>
cc: nickpiggin@yahoo.com.au, Jeff Garzik <jgarzik@pobox.com>,
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       linux-kernel@vger.kernel.org
Subject: RE: Anticipatory prefaulting in the page fault handler V1
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On Wed, 8 Dec 2004, Luck, Tony wrote:

> >If a fault occurred for page x and is then followed by page
> >x+1 then it may be reasonable to expect another page fault
> >at x+2 in the future.
>
> What if the application had used "madvise(start, len, MADV_RANDOM)"
> to tell the kernel that this isn't "reasonable"?

We could use that as a way to switch of the preallocation. How expensive
is that check?