Re: gettimeofday() system call timing curiosity

From: Davide Libenzi (davidel@xmailserver.org)
Date: Fri Mar 08 2002 - 15:30:26 EST


On Fri, 8 Mar 2002, Jamie Lokier wrote:

> It's the _median_ that varies from 453 to 470, not the _mean_, so the
> accumulation to 17000 cycles doesn't apply.

I was doing something similar and i got huge numbers out of a small mean.
It was the recalc loop that hit inside the scheduler or in this case it
could be a schedule() entry due a need_resched set by the timer. From the
number of cycles it seems possible.

- Davide

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