Re: a faster way to gettimeofday? rdtsc strangeness

From: Terje Eggestad (terje.eggestad@scali.com)
Date: Thu Mar 07 2002 - 10:43:35 EST


On Thu, 2002-03-07 at 15:41, Alan Cox wrote:
> > If you have a CPU that begin throttling it usually cut the CPU clock in
> > half and the rdtsc counter count half a fast.
>
> They normally adjust the STPCLK which is just fine. I've only seen a few
> laptops that do it other ways. More fun are people running mixed 300/450
> BP6 boards where the tsc varies by cpu

Can /proc/cpuinfo really be trusted in figuring out how long a cycle is?

-- 
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Terje Eggestad mailto:terje.eggestad@scali.no Scali Scalable Linux Systems http://www.scali.com

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