Re: 2.6.11 timeval_to_jiffies() wrong for ms resolution timers

[George Anzinger]

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@xxxxxxxxxx
High-res-timers:  http://sourceforge.net/projects/high-res-timers/
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