Re: Possible spin-problem in nanosleep()

[Richard B. Johnson]

On Thu, 23 Jun 2005, Andreas Schwab wrote:

> "Richard B. Johnson" <linux-os@xxxxxxxxxxxx> writes:
>
> > nanosleep() appears to have a problem. It may be just an
> > 'accounting' problem, but it isn't pretty. Code that used
> > to use usleep() to spend most of it's time sleeping, used
> > little or no CPU time as shown by `top`. The same code,
> > converted to nanosleep() appears to spend a lot of CPU
> > cycles spinning. The result is that `top` or similar
> > programs show lots of wasted CPU time.
>
> usleep() is just a wrapper around nanosleep().  Are you sure you got the
> units right?
>
> Andreas.

Yeah nano is -9 micro is -6, three more zeros when using nano.
I note that the actual syscall is __NR_nanosleep = 162. I don't
understand the discrepancy either.

> --
> Andreas Schwab, SuSE Labs, schwab@xxxxxxx
> SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
> Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
> "And now for something completely different."

Cheers,
Dick Johnson
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