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Subject: Re: How is user space notified of CPU speed changes?
From: Lee Revell <rlrevell@joe-job.com>
To: Chris Friesen <cfriesen@nortelnetworks.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Robert Love <rml@novell.com>
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On Fri, 2004-10-22 at 15:40, Chris Friesen wrote:
> Lee Revell wrote:
> 
> > Seems like you are implying that any userspace app that needs to know
> > the CPU speed is broken.  Is this correct?
> 
> No, we're saying that Intel's tsc implementation is broken.  <grin>
> 
> x86 really could use an on-die register that increments at 1GHz independent of 
> clock speed and is synchronized across all CPUs in an SMP box.

Well, it looks like we can just fix JACK to not use the TSC for timing. 
Seems like the current design is fundamentally incompatible with CPU
scaling.

Lee

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