Messages in this thread | | | Subject | Re: periods and deadlines in SCHED_DEADLINE | From | Luca Abeni <> | Date | Sat, 10 Jul 2010 09:11:47 +0200 |
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On Fri, 2010-07-09 at 16:24 +0200, Peter Zijlstra wrote: > On Fri, 2010-07-09 at 15:38 +0200, Raistlin wrote: > > Basically, from the scheduling point of view, what it could happen is > > that I'm still _NOT_ going to allow a task with runtime Q_i, deadline > > D_i and period P_i to use more bandwidth than Q_i/P_i, I'm still using D > > for scheduling but the passing of the simple in-kernel admission test > > Sum_i(Q_i/P_i)<1 won't guarantee that the task will always finish its > > jobs before D. > > But the tardiness would still be bounded, right? So its a valid Soft-RT > model? I think that if Sum_i(Q_i/P_i)<1 but Sum_i(Q_i/min{P_i,D_i})>=1 then you can have sporadic deadline misses, but it should still be possible to compute an upper bound for the tardiness. But this is just a feeling, I have no proof... :)
Luca
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