Re: [linux-audio-user] Re: favorite window Manager for making music?

On Tue, 2006-02-21 at 20:49 -0500, Lee Revell wrote:
> On Tue, 2006-02-21 at 19:30 -0600, Jan Depner wrote:
> > On Tue, 2006-02-21 at 15:28 -0500, Lee Revell wrote:
> > > On Tue, 2006-02-21 at 13:19 -0600, Jan Depner wrote:
> > > > There's a bunch of information on that on my site (albeit outdated).
> > > > Tuning the disk drives is a must and it *will* help but there are
> > > > instances where the disk drive is busy and you can't get to it no
> > > > matter
> > > > how well tuned it is. I prefer to minimize any chance of that. You
> > > > have to remember that unless you're running RTLinux or VXWorks (or DOS
> > > > or VMS) you're not running a hard real time system. Shit happens.
> > > >
> > >
> > > The -rt kernel with fuill preemption actually is a hard real time system
> > > (no one claims it is in the same league of reliability as QNX or
> > > VXWorks, yet...) - it should be able to guarantee response times.
> > >
> >
> > While I agree that it's very good it's not hard real-time. It can't
> > do guaranteed 15 microsecond interrupt response. It is a very good soft
> > real-time system.
> >
>
> Hard RT is not about what the response time is, it's about whether you
> can guarantee to make some arbitrary deadline, which the -rt patch can
> theoretically do (I say theoretically because you still would have to
> audit a limited set of code paths for RT safeness).
>

    I beg to differ. Hard real-time guarantees the response time. Most
good hard real-time systems actually do respond in the 10-15 microsecond
range (though that is not a requirement of hard real-time). Theory has
no place in hard real-time. Check with Monta Vista and see if they
think the kernel with RT patches is hard real-time.

-- 
Jan 'Evil Twin' Depner
The Fuzzy Dice
http://myweb.cableone.net/eviltwin69/fuzzy.html
"As we enjoy great advantages from the invention of others, we should be 
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