Re: [PATCH][RSDL-mm 0/7] RSDL cpu scheduler for 2.6.21-rc3-mm2

Con Kolivas
2007-03-13T09:41:28Z

On Tuesday 13 March 2007 20:29, Ingo Molnar wrote:
> * Con Kolivas <kernel@kolivas.org> wrote:
> > Well I guess you must have missed where I asked him if he would be
> > happy if I changed +5 metrics to do whatever he wanted and he refused
> > to answer me. [...]
>
> I'd say lets keep nice levels out of this completely for now - while
> they should work _too_, it's easy because the scheduler has the 'nice'
> information. The basic behavior of CPU hogs that matters most.
>
> So the question is: if all tasks are on the same nice level, how does,
> in Mike's test scenario, RSDL behave relative to the current
> interactivity code?

If everything is run at nice 0? (this was not the test case but that's what
you've asked for).

We have:
X + GForce contribute a load of 1
lame x 2 threads contribute a load of 2

In RSDL
X + GForce will get 33% cpu
lame will get 66% cpu

In mainline
X + GForce gets a fluctuating percentage somewhere between 35~45% as far as I
can see on UP.
lame gets the rest

The only way to get the same behaviour on RSDL without hacking an
interactivity estimator, priority boost cpu misproportionator onto it is to
either -nice X or +nice lame.

> Ingo

--
-ck