Re: Scheduler degradation since 2.5.66

[George Anzinger]

Jamie Lokier wrote:
> George Anzinger wrote:
>
> > Try running the test with a requested sleep time of something less than 
> > 0.999849 ms.  All this is for the x86 which is using this time to do the 
> > best it can with the PIT which can only get this close to 1 ms ticks.  You 
> > can even vary this number to see exactly where the round up actually 
> > happens.  Ah, life in the nano world :)
>
>
> Would it be better to program the PIT for lowest frequency that's >= 1.0ms.

Possibly.  I haven't attempted to analize it.  I do know it would make some of 
the math a bear.  Integers like to round down (read truncate) so...  But then, 
what we have isn't exactly fun :)

--
George Anzinger   george@xxxxxxxxxx
High-res-timers:  http://sourceforge.net/projects/high-res-timers/
Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml

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