Re: [CFT][PATCH] new scheduler policy

Nick Piggin
2003-08-19T16:21:41Z

Mike Galbraith wrote:

> At 11:53 AM 8/19/2003 +1000, Nick Piggin wrote:
>
>> Hi everyone,
>>
>> 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
>
>
> Ok, I took it out for a quick spin...

Thanks again.

>
> Test-starve.c starvation is back (curable via other means), but irman2
> is utterly harmless. Responsiveness under load is very nice until I
> get to the "very hefty" end of the spectrum (expected). Throughput is
> down a bit at make -j30, and there are many cc1's running at very high
> priority once swap becomes moderately busy. OTOH, concurrency for the
> make -jN in general appears to be up a bit. X is pretty choppy when
> moving windows around, but that _appears_ to be the newer/tamer
> backboost bleeding a kdeinit thread a bit too dry. (I think it'll be
> easy to correct, will let you know if what I have in mind to test that
> theory works out). Ending on a decidedly positive note, I can no
> longer reproduce priority inversion troubles with xmms's gl thread,
> nor with blender.

Well, it sounds like a good start, though I'll have to get up to scratch
on the array of scheduler badness programs!

I expect throughput to be down in this release due to the timeslice thing.
This should be fixable.

I think either there is a bug in my accounting somewhere or I have not quite
thought it though properly because priorities don't seem to get distributed
well. Also its not using the nanosecond timing stuff (yet). This might help
a bit.

Nick