Re: 2.6.11 timeval_to_jiffies() wrong for ms resolution timers

[Chris Friesen]

George Anzinger wrote:
> Bhavesh P. Davda wrote:
> > setitimer for 20ms was firing at 21ms

> If we do NOT account for this PIT issue, the result is a time drift that 
> is outside of what ntp can handle...

Still, it is non-intuitive that a multi-GHz machine can't wake you up 
more accurately than 1ms.

What about telling it to wake up a jiffy earlier, then checking whether 
the scheduling lag was enough to cause it to have waited the full 
specified time.  If not, put it to sleep for another jiffy.

Chris
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/