On Mon, Dec 12, 2022 at 09:11:36PM +0100, Peter Zijlstra wrote: > > > Hurmph.. this further propagate the existing problem of thinking that > > > 'prio' is a useful concept in general (it isn't). > > > > I'm not quite following. Can you please expand on why prio isn't a generally > > useful concept? > > The whole fixed vs dynamic priority scheduling thing. Specifically > SCHED_DEADLINE implements a dynamic priority scheme using the sporadic > task model which just doesn't map well to this single prio value > (notably every SCHED_DEADLINE task has prio -1, making it impossible to > order SCHED_DEADLINE tasks based on this). I see, so the expressive power isn't sufficient to cover some use cases. Yeah, I mean, it's limited and we can add whatever that's necessary but given that there are many use cases that make use of priorities, I don't think SCX can skip supporting it. Thanks. -- tejun
