Re: RT patch acceptance

Lee Revell
2005-05-31T21:52:31Z

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.

Only the engineer who designs the system knows for sure, so if the RT
app people say PREEMPT_RT is good enough for a *very* large set of the
applications that they currently need a commercial RTOS for, they should
be given the benefit of the doubt. To say otherwise is to assert that
you know their hardware (be it desktop PC, digital audio workstation, or
airplane) better than they do.

Lee