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Date: Wed, 22 Nov 2006 21:16:25 +0100
From: Ulrich Spoerlein <uspoerlein@gmail.com>
To: Alan Cox <alc@cs.rice.edu>
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Cc: Kip Macy <kip.macy@gmail.com>, arch@freebsd.org
Subject: Re: superpage plans
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Alan Cox wrote:
> Lastly, page coloring dies.  However, the beneficial effects of page coloring are for the 
> most part captured by superpages.  Specifically, regardless of whether the pmap is able to 
> promote a particular region of the address space to a superpage, e.g., due to heterogenous 
> access rights of pages within the region, if the memory has been provided by the reservation 
> system it will have "perfect" coloring.

Hi Alan,

what performance impact do you estimate for "older" processors? I know
very little about superpages, so I assume that, e.g., earlier Pentiums
don't support it? Where do you think the break off point lies?

Ulrich Spoerlein
-- 
A: Yes.
>Q: Are you sure?
> >A: Because it reverses the logical flow of conversation.
> >>Q: Why is top posting frowned upon?