Re: PREEMPT_RT vs I-PIPE: the numbers, part 2

[Karim Yaghmour <karim@opersys.com>]

Lee Revell wrote:
> Well, if you want to be even more fair, you could hold off on publishing
> benchmark results that compare an experimental, not fully debugged
> feature with a mature technology.

Would you have applied similar logic had the results been inverted?

Surely the nature of scientific improvement is somewhere along
the lines of experiment, compare, enhance, and retry.

If PREEMPT_RT should not be studied, then what good is it to
continue talking about it on the LKML or even to continue posting
the patches there?

Surely the goal in doing that is to make it better and more
acceptable to the larger crowd. And if that is so, then isn't
it to everyone's advantage therefore to make a strong case for
its adoption?

Did you really expect that no one was going to start running
performance tests on preemp_rt somewhere along the way until
its developers gave an "official" ok? Isn't it better to know
about such results sooner rather than later?

... I'm sorry, I'm somewhat lost here. I can just guess that
you're expressing your dissapointment at the results, and
that's something I can understand very well. But shouldn't
these results encourage you try even harder? Lest you are
telling me that that's as good as it gets ... ?

As a side note about the I-pipe (formerly Adeos), it should
be noted that, in as far as I can recall, its latency response
and performance impact have not varied a lot since its first
introduction over 3 years ago. The mechanism's simplicity
makes it unlikely to introduce any sort of significant
overhead.

Karim
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