Re: RT patch acceptance

Zwane Mwaikambo
2005-06-01T02:37:07Z

On Tue, 31 May 2005, Steven Rostedt wrote:

> On Tue, 2005-05-31 at 17:47 -0400, Lee Revell wrote:
> > On Tue, 2005-05-31 at 17:22 -0400, Steven Rostedt wrote:
> > > I wouldn't call RTAI, RTLinux or a nano-kernel (embedded with Linux)
> > > "Diamond" hard. Maybe "Ruby" hard, but not diamond. Remember, I use to
> > > test code that was running airplane engines, and none of those mentioned
> > > would qualify to run that.
> >
> > I think trying to make these types of distinctions is a waste of time.
> > What matters is the MTBF of the software relative to the hardware on a
> > given system. It would be stupid to use a commercial RTOS for a cell
> > phone because they fall apart in a year anyway and users don't seem to
> > care. Ditto anything running on PC hardware. For an airplane the MTBF
> > obviously must be more in line with that hardware which hopefully is way
> > more reliable.
>
> Agreed. I only brought up the stupid names just to show that there's
> not a black and white aspect to what RT is. It's mainly a black art
> since there's no way to know how many bugs a program has, and how do you
> truly calculate the MTBF, other than running it on the hardware itself?

This discussion has digressed even further beyond hard/soft realtime
to reliability and fault tolerance (airplane engine), which is not
the same thing.