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Date: Tue, 23 Dec 2008 17:56:00 +0000
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Len Brown <lenb@kernel.org>
Cc: Zdenek Kabelac <zdenek.kabelac@gmail.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       cpufreq@vger.kernel.org
Subject: Re: Perfomance governor is still changing frequency
Message-ID: <20081223175600.GB17426@srcf.ucam.org>
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On Mon, Dec 15, 2008 at 12:59:15PM -0500, Len Brown wrote:

> and that will tell us if turbo is related to your
> occasional obervance of low-frequency-mode.

We've observed this on certain other pieces of modern Intel hardware - 
the best hypothesis we've been able to come up with is that if the msr 
read is the first instruction run on the core when it's previously been 
in a deep C state, the low-clock speed is reported. However, some 
Thinkpads will also automatically limit their speed for thermal reasons.

-- 
Matthew Garrett | mjg59@srcf.ucam.org
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