From: "Ray Bryant" <raybry@mpdtxmail.amd.com>
To: "Andi Kleen" <ak@suse.de>
Subject: Re: [discuss] Re: [PATCH] x86-64: Fix bad assumption that
 dualcore cpus have synced TSCs
Date: Wed, 21 Sep 2005 10:46:25 -0500
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On Wednesday 21 September 2005 10:04, Andi Kleen wrote:

>
> We handle this, but single socket dual core was special cased because
> I was told previously it should be ok.
>
> -Andi

AFAIK there is a processor state bit that enables/disables this behavior.
Apparently some BIOS's are setting this one way for desktop systems and the 
other way for servers.   If it is thought to be important I can track that 
down and see if it can be externally documented.  (It may actually be in the 
bios and kernel developer guide...)

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

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