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SubjectRe: 2.6.11 timeval_to_jiffies() wrong for ms resolution timers
Chris Friesen wrote:
> 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.

The user is, of course, free to do what ever they would like. For a more
complete solution you might be interested in HRT (High Res Timers). See my
signature below.
>
--
George Anzinger george@mvista.com
High-res-timers: http://sourceforge.net/projects/high-res-timers/
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