Messages in this thread | | | Date | Thu, 7 Jan 2010 08:47:00 -0600 | From | Clark Williams <> | Subject | Re: [RFC] [rt-tests] change to cyclictest behavior |
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On Thu, 07 Jan 2010 08:23:52 +0100 Carsten Emde <Carsten.Emde@osadl.org> wrote:
> Clark, > > >> -S --smp Standard SMP testing (equals -a -t -n -d0), > >> same priority on all threads. > After having done some tests with a quickly hacked cyclictest version, I > have found an issue with including -d0. Apparently, small numbers make > life especially difficult for the scheduler; this is why we often used > -d1. Specifying -d0 seems a special case where all threads are in sync. > Maybe, we may miss some important latency constellations, if we do not > let the tasks slightly interfere. In any case, I would like to be able > to specify a distance _in addition_ to -S. This would create a scenario > where > > cyclictest -d1 -S > > results in a distance of 0, and > > cyclictest -S -d1 > > results in a distance of 1. Would this be acceptable? > > Carsten.
I don't have a problem not having -d in the -S option. I was looking at the possibility of synchronous sampling as well so it's probably a good idea to keep it separate.
The main things we want are implied -t, -a and -n.
Clark [unhandled content-type:application/pgp-signature] | |