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DateMon, 15 Dec 2003 23:45:48 -0800
FromGeorge Anzinger <>
SubjectRe: Scheduler degradation since 2.5.66
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@mvista.com
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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