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Subject: Re: [PATCH] tsc-disable_B9
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "Martin J. Bligh" <Martin.Bligh@us.ibm.com>
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On Mon, 2002-08-26 at 19:45, Martin J. Bligh wrote:
> It's not correlating it to real time that's the problem. It's getting resceduled
> inbetween calls that hurts. Take your example.
> 
> rdtsc
> mov %eax,%ebx
> 			<- get rescheduled here
> rdtsc
> 
> Broken. May even take negative "time".

Statistically irrelevant. When you have 100,000 samples all the
pre-emption ones drop into the dud sample filter with IRQ disturbance
and so on.


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