Re: [PATCH] schedule: SCHED_RR: Give a fresh time-slice to the task after after it suspends or relinquishes

[Zhaoxiu Zeng]

Peter Zijlstra <peterz@xxxxxxxxxxxxx> 于2021年12月22日周三 18:41写道：
>
> On Wed, Dec 22, 2021 at 05:15:26PM +0800, zhaoxiu.zeng wrote:
> > Assuming the sched_rr_timeslice is 100ms, there are several tasks with the
> > same priority t1, t2, t3, ..., and t1 sleeps every 80ms, the scheduling
> > timing may be:
> >     t1  t2   t3        t1  t2   t3        t1  t2   t3        t1  t2   t3
> >     80, 100, 100, ..., 20, 100, 100, ..., 60, 100, 100, ..., 40, 100, 100
> >
> > After applying this patch, the scheduling timing may be:
> >     t1  t2   t3        t1  t2   t3        t1  t2   t3        t1  t2   t3
> >     80, 100, 100, ..., 80, 100, 100, ..., 80, 100, 100, ..., 80, 100, 100
> >
>
> Is this what POSIX mandates or why are you sending this to me ?

Thanks for your reply!

I don't see a definition of this in POSIX.
Give a fresh time-slice may decreases context switches, and be more
fairly to the tasks which suspended then resumed.