Messages in this thread | | | Subject | Re: [patch v5 06/15] sched: log the cpu utilization at rq | From | Peter Zijlstra <> | Date | Wed, 20 Feb 2013 16:20:31 +0100 |
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On Wed, 2013-02-20 at 22:33 +0800, Alex Shi wrote: > > There's generally a better value than 100 when using computers.. > seeing > > how 100 is 64+32+4. > > I didn't find a good example for this. and no idea of your suggestion, > would you like to explain a bit more?
Basically what you're doing ends up being fixed point math, using 100 as unit is inefficient, pick a power-of-2 and everything reduces to bit-shifts.
http://en.wikipedia.org/wiki/Fixed-point_arithmetic
So use 128 or 1024 or whatever and you don't need mult and div instructions to represent [0,1]
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