Re: a joint letter on low latency and Linux

[Richard Gooch]

Larry McVoy writes:
> > I am nervous about this characterization. As I have said many times,
> > "hard realtime" normally *implies* a lot more than we need for
> > real-time audio+MIDI applications. All we need is guaranteed
> > scheduling response. We don't need QOS guarantees for any other
> > subsystems, for example (it would be nice, but its not necessary).
> 
> "All we need is guaranteed scheduling response".  But it's not real
> time.
> 
> Those two statements are 100% at odds with each other.

Not if you read it this way: "we want feature XYZ, but we won't call
it RT, because then people will tell us to use RTLinux, and we don't
want to do that.".

I think people advocating the scheduling/preemption hacks should go
and run some exhaustive tests to find out how bad the latency can be
with said patch, and then identify where the remaining latencies are
coming from. Then fix the worst offender and run the tests again.

My guess is you'll be digging yourself in deeper and deeper,
sprinkling random hacks in random places, as Linus put it.

				Regards,

					Richard....
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