[linux-audio-dev] Re: desktop and multimedia as an afterthought?

[Martijn Sipkema]

From: "Christian Henz" <chrhenz at gmx.de>
> On Tue, Jul 13, 2004 at 10:55:48AM -0400, Paul Davis wrote:
> > >Thus, the fact that Linux does not support protocols to prevent priority
> > >inversion (please correct me if I am wrong) kind of suggests that supporting
> > >realtime applications is not considered very important.
> > 
> > we went through this (you and i in particular) right here on LAD a
> > year or so ago. while i might agree with you about the priority given
> > to RT-ish apps, my recollection of the end of that discussion is that
> > priority inheritance is neither necessary nor sufficient to allow
> > adequate RT performance. priority inversion generally can be factored
> > out through application redesign, and the protocols i've seen to
> > address it are not useful for RT purposes - they just help deadlock.
> > 
> 
> Hmm, I've just recently learned about the Priority Ceiling Protocol,
> an extension to Priority Inversion Protocol, which explicitly prevents
> deadlocks. And I've learned about both in a RTOS course, so I'm a little
> surprised by your statement about them not being useful for RT purposes :-)

They are meant for realtime use and are part of the POSIX realtime
extensions, so I disagree with Paul. That's not uncommon, though we
have agreed on some things in the past. :)

--ms