Re: [PATCH] O13int for interactivity

[Con Kolivas <kernel@kolivas.org>]

On Tue, 5 Aug 2003 19:09, Mike Galbraith wrote:
> At 06:43 PM 8/5/2003 +1000, Con Kolivas wrote:
> >On Tue, 5 Aug 2003 18:27, Mike Galbraith wrote:
> > > At 06:20 PM 8/5/2003 +1000, Con Kolivas wrote:
> > > >Every experiment I've tried at putting tasks at the start of the queue
> > > >instead
> > > >of the end has resulted in some form of starvation so should not be
> > > > possible for any user task and I've abandoned it.
> > >
> > > (ditto:)
> >
> >Superuser access real time tasks may be worth reconsidering though...
>
> If they were guaranteed ultra-light, maybe, but userland is just not
> trustworthy.

Agreed 

> Better imho would be something like Davide's SOFT_RR with an additional
> automatic priority adjust per cpu usage or something (cpu usage being a
> [very] little bit of a latency hint, and a great 'hurt me' hint).  Best
> would be an API that allowed userland applications to describe their
> latency requirements explicitly, with the scheduler watching users of this
> API like a hawk, ever ready to sanction abusers.  Anything I think about in
> this area gets uncomfortably close to hard rt though, and all of the wisdom
> I've heard on LKLM over the years wrt separation of problem spaces comes
> flooding back.

I'll pass. There's enough on my plate already. Soft_rr in some form is a 
decent idea but best tackled separately.

Con