Messages in this thread | | | Date | Fri, 14 Jul 2006 22:31:41 +0100 (BST) | Subject | Re: Where is RLIMIT_RT_CPU? | From | Esben Nielsen <> |
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On Fri, 14 Jul 2006, Jean-Marc Valin wrote:
>> It was not merged. >> >> This problem should be addressed by a userspace RT watchdog. Ubuntu >> should not have shipped their system with unlimited non-root realtime >> enabled and no watchdog. > > Does such a daemon currently exist? Even then, is there any way to > police all unprivileged RT apps without introducing an O(N) operation > running continuously at max rt priority? Sort of defeats the purpose of > having an O(1) scheduler, no? I assume the RT check can be some in O(1) > time in the kernel, right? >
Can't you just make a prio 1 task which signals a prio 99 once say every second. If the priority 99 task doesn't get the signal after say 2 seconds, it will look for a rt task running wild. At worst it will have to do an O(n) algorith when things have gone wrong, not when everything is working.
Esben
> About Ubuntu, I agree it wasn't a smart thing to do (I'm not an Ubuntu > devel, so I don't know what the reason was), but it would be nice if > this could be fixed without having to entirely remove the unprivileged > real-time feature. In the end, I'm not sure what the best solution is > (just an RT audio developer). > > Jean-Marc > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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