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

Bill Huey
2005-06-20T18:25:23Z

On Mon, Jun 20, 2005 at 01:13:32PM -0400, Kristian Benoit wrote:
> For PREEMPT_RT clearly the results are much better than last time.
> Indeed it appears that, as Ingo predicted, a combination of the
> proper configuration options and most recent additions gives
> PREEMPT_RT important gains. In comparison to last week's results
> all measures are lower: average response time, maximum response time,
> minimum response time, and standard deviation. This is very good.
> But that's not all. PREEMPT_RT also comes down virtually neck-to-
> neck with the I-pipe (and the previous numbers from Adeos) in
> terms of maximum interrupt response time. Certainly those backing
> PREEMPT_RT, and others we hope, will find this quite positive.

You might what to try the overall times numbers with the voluntary
preemption instead. That option doesn't convert spinlocks and still
uses interrupt threads. I'd be surprised that the spinlocks would
contribute to that much overhead. Nevertheless, I'll be curious
about those results.

bill