From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Nikita V. Youshchenko" <yoush@cs.msu.su>
Subject: Re: preempt rt in commercial use
Date: Tue, 14 Sep 2010 18:30:02 +0400
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Cc: Robert Schwebel <r.schwebel@pengutronix.de>,
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To: Jeff Angielski <jeff@theptrgroup.com>
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> >> anyone can say preempt rt is hard real time?
> >
> > Hard realtime has something to do with how you define "missing the
> > deadline". If somebody cuts the cable of your roboter controller in
> > the factory hall, the system misses the deadline. So it is all about
> > probabilities: hard realtime systems have a very, very low probability
> > of missing the deadline. However, in real life systems, it is>  0%.
> >
> > So yes, if you talk about real world, it is hard realtime.
>
> No.  Preempt rt it's not hard realtime.
>
> But most people/companies who think they need hard realtime really
> don't.  They can live with soft realtime and have a really low
> probability of missing deadlines and having long latencies.  For these
> people, the preempt rt is adequate.

Isn't any case where preempt-rt does not behave as hard reatlime a bug in 
preempt-rt, that should be reported to this list and eventually fixed?