Messages in this thread | | | Date | Thu, 23 Jun 2005 08:46:30 -0400 (EDT) | From | "Richard B. Johnson" <> | Subject | Re: Possible spin-problem in nanosleep() |
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On Thu, 23 Jun 2005, Andreas Schwab wrote:
> "Richard B. Johnson" <linux-os@analogic.com> 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@suse.de > 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." >
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