Re: [ANNOUNCE] RSDL completely fair starvation free interactive cpu scheduler

From: Con Kolivas
Date: Sun Mar 04 2007 - 16:49:56 EST


On Monday 05 March 2007 07:35, Al Boldi wrote:
> Con Kolivas wrote:
> > > >> >> >This message is to announce the first general public release of
> > > >> >> > the "Rotating Staircase DeadLine" cpu scheduler.
>
> Thanks a lot!

You're welcome.
>
> > Just to make it clear. The purpose of this scheduler is at all costs to
> > maintain absolute fairness no matter what type of load it is put under.
>
> Great!
>
> > This means that if you heavily load up your machine without the use of
> > 'nice' then your interactive tasks _will_ slow down proportionately to
> > the amount of cpu you use. So doing make -j4 for example will make any
> > other task started in taht presence run precisely 1/5th speed, but they
> > will still be responsive, have low latency (and audio shouldn't skip for
> > example).
>
> That's just what it did, but when you "nice make -j4", things (gears) start
> to stutter. Is that due to the staircase?

gears isn't an interactive task. Apart from using it as a background load to
check for starvation because it loads up the cpu fully (which a gpu intensive
but otherwise simple app like this should _not_ do) graphics card drivers and
interrupts and so on, I wouldn't put much credence on gears as anything else.
However I suspect that gears will still get a fair share of the cpu on RSDL
which almost never happens on any other scheduler.

P.S. Al, please don't drop ccs from the original thread.

--
-ck
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