Re: [RFC][PATCH][2.6.6] Replacing CPU scheduler active and expired with a single array

[Ingo Molnar]

* Peter Williams <peterw@xxxxxxxxxx> wrote:

> >just try it - run a task that runs 95% of the time and sleeps 5% of the
> >time, and run a (same prio) task that runs 100% of the time. With the
> >current scheduler the slightly-sleeping task gets 45% of the CPU, the
> >looping one gets 55% of the CPU. With your patch the slightly-sleeping
> >process can easily monopolize 90% of the CPU!
> 
> If these two tasks have the same nice value they should around robin
> with each other in the same priority slot and this means that the one
> doing the smaller bites of CPU each time will in fact get less CPU
> than the other i.e. the outcome will be the opposite of what you
> claim.

just try what i described with and without your patch and look at the
'top' output. You can do a simple loop plus short 10-20msec sleeps (via
nanosleep) to simulate a 95% busy task.

	Ingo
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