Messages in this thread | | | Date | Thu, 22 May 2003 13:47:35 -0700 | Subject | Re: Linux 2.4 scheduler is RTOS-alike? | From | Elladan <> |
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Also of note, FIFO threads will actually block the same priority threads forever. An RR thread will also block a lower priority thread forever, but it'll get preempted by other RR threads with the same priority. A FIFO thread is never preempted except by higher priority, it has to yield somehow (explicitly or by blocking)
-J
On Thu, May 22, 2003 at 01:01:30PM -0700, Ming Lei wrote: > > will it be the same behavior If thread A and thread B both have a lot of > printf? Suppose A get first run, does B get run at all? > > > this question is regarding linux kernel 2.4.7-2.4.20. > > linux 2.4 kernel does support real time sheduler. If using FIFO real time > > schedule policy, would the case that higher priority thread starve the > lower > > priority thread happen? Similarly, let's say an example: if I have higher > > prioority thread A and lower priority thread B, thread A is running > without > > any wait or blocking, is there a possiblity that 2.4 scheduler may want to > > switch to thread B? Why? > > Yes, FIFO threads that spin will block lower priority threads forever. > > Sure, guaranteed if the high prio SCHED_FIFO task doesn't block at all. If > you have a pure cpu burner, it will starve all lower priority > threads. - 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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