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From: "Ray Bryant" <raybry@mpdtxmail.amd.com>
To: "Dave McCracken" <dmccr@us.ibm.com>
Subject: Re: [PATCH/RFC] Shared page tables
Date: Mon, 23 Jan 2006 18:16:38 -0600
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On Monday 23 January 2006 17:58, Ray Bryant wrote:
<snip>

> ... And what kind of alignment constraints do we end up
> under in order to make the sharing happen?   (My guess would be that there
> aren't any such constraints (well, page alignment.. :-)  if we are just
> sharing pte's.)
>

Oh, obviously that is not right as you have to share full pte pages.   So on 
x86_64 I'm guessing one needs 2MB alignment in order to get the sharing to
kick in, since a pte page maps 512 pages of 4 KB each.

Best Regards,
-- 
Ray Bryant
AMD Performance Labs                   Austin, Tx
512-602-0038 (o)                 512-507-7807 (c)

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