On Tue, 2005-01-18 at 10:17 -0600, Jack O'Quin wrote: > Cal <[EMAIL PROTECTED]> writes: > > > There's a collection of test summaries from jack_test3.2 runs at > > <http://www.graggrag.com/ck-tests/ck-tests-0501182249.txt> > > > > Tests were run with iso_cpu at 70, 90, 99, 100, each test was run > > twice. The discrepancies between consecutive runs (with same > > parameters) is puzzling. Also recorded were tests with SCHED_FIFO and > > SCHED_RR. > > It's probably suffering from some of the same problems of thread > granularity we saw running nice --20. It looks like you used > schedtool to start jackd. IIUC, that will cause all jackd processes > to run in the specified scheduling class. JACK is carefully written > not to do that. Did you also use schedtool to start all the clients? > > I think your puzzling discrepancies are probably due to interference > from non-realtime JACK threads running at elevated priority.
Isn't this going to be a showstopper? If I understand the scheduler correctly, a nice -20 task is not guaranteed to preempt a nice -19 task, if the scheduler decides that one is more CPU bound than the other and lowers its dynamic priority. The design of JACK, however, requires the higher priority threads to *always* preempt the lower ones. Lee - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
