Re: [CFT][PATCH] new scheduler policy

Nick Piggin
2003-08-19T03:00:49Z

Nick Piggin wrote:

>
>
> William Lee Irwin III wrote:
>
>> On Tue, Aug 19, 2003 at 11:53:01AM +1000, Nick Piggin wrote:
>>
>>> As per the latest trend these days, I've done some tinkering with
>>> the cpu scheduler. I have gone in the opposite direction of most
>>> of the recent stuff and come out with something that can be nearly
>>> as good interactivity wise (for me).
>>> I haven't run many tests on it - my mind blanked when I tried to
>>> remember the scores of scheduler "exploits" thrown around. So if
>>> anyone would like to suggest some, or better still, run some,
>>> please do so. And be nice, this isn't my type of scheduler :P
>>> It still does have a few things that need fixing but I thought
>>> I'd get my first hack a bit of exercise.
>>> Its against 2.6.0-test3-mm1
>>>
>>
>> Say, any chance you could spray out a brief explanation of your new
>> heuristics?
>>
>
> Oh alright. BTW, this one's not for your big boxes yet! It does funny
> things with timeslices. But they will be (pending free time) made much
> more dynamic, so it should _hopefully_ context switch even less than
> the normal scheduler in a compute intensive load.
>
> OK. timeslices: they are now dynamic. Full priority tasks will get
> 100ms, minimum priority tasks 10ms (this is what needs fixing, but
> should be OK to test "interactiveness")
>
> interactivity estimator is gone: grep -i interactiv sched.c | wc -l
> gives 0.
>
> priorities are much the same, although processes are supposed to be
> able to change priority much more quickly.
>
> backboost is back. that is what (hopefully) prevents X from starving
> due to the quickly changing priorities thing.

And lack of interactivity estimator.