Re: [AD] Add timeBeginPeriod(1) to wtimer.c

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On my winXP athlon64 3000+ machine.
setting the timeBeginPeriod(1) once globally results in much better performance. possibly due to better timing.

aj.




Chris wrote:
Elias Pschernig wrote:

Not sure how high the cost would be, even in case it would work like I
think. I only know the linux scheduler has 10ms tickss, and uses every
2nd tick to do scheduling (or something like that, didn't pay enough
attention in lectures :P) - and there must be a reason they don't use
1ms ticks.


I believe there's a kernel option to change the frequency of the timer. At least, I remember seeing one in an older (pre-2.4.28) version. 2.4.28 does, however, have a Low-latency scheduler option (which is off by default).. I haven't been able to test it, though.

But on my old 400MHz machine, I remember changing the timer option from 100 to 1000, and my system became almost unuseable because it was so unrepsonsive. I fear the same thing is happening with timeBeginPeriod(1). Faster CPU's may not show as much speed defficiency (and perhaps at some point, it'll become more efficient), but I don't think current CPUs are ready for it, hence why the scheduler is still 10ms by default.


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