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SubjectRe: gettimeofday() system call timing curiosity
Jamie Lokier wrote:

>
> On my laptop, the median of rdtsc+gettimeofday+rdtsc times is 470 cycles
> for most runs of 1000, but is occasionally 453 cycles.
>


What that indicates to me is that 1000 is way too small of a sample.
You're only talking a difference of 17,000 cycles, which could --
especially with cache effects -- easily be the time spent in an
interrupt handler.

-hpa



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