On Thu, 7 Jul 2005, Ingo Molnar wrote: > > Still looking into this issue on -51-06. Found something really odd: > > SCHED_NORMAL tasks will start to inherit the priority value of some > > other SCHED_FIFO task. If JACK is started at a given SCHED_FIFO > > priority, X and all of its children will inherit the same priority > > value after login. Other random processes will inherit this, too -- > > sometimes init... > > > > SCHED_NORMAL tasks suddenly inheriting priority values in the range > > normally reserved for SCHED_FIFO could explain at least part of the > > meltdown I've been seeing. Any thoughts? > > is this inheritance perpetual? It is normal for some tasks to be boosted > momentarily, but if the condition remains even after jackd has exited, > it's clearly an anomaly. (lets call it "RT priority leakage".) Priority > leakage on SMP was fixed recently, but there could be other bugs > remaining.
Yes, this leakage perpetual. That's what struck me as odd. > There's priority-leakage debugging code in the -RT kernel, which is > activated if you enable CONFIG_DEBUG_PREEMPT. This debugging code, if > triggered, should produce 'BUG: comm/123 leaked RT prio 123 (123)?" type > of messages. But ... due to a bug it would not print out anything but > would lock up hard if it detects the condition (and if > RT_DEADLOCK_DETECT is enabled). I have fixed this reporting bug in the > -51-08 kernel. -51-08 is building now. I'll check out the latest, too. --ww - 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/
