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Date: Thu, 29 Dec 2011 18:12:56 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Kirill Tkhai <kirill.tkhai@gmail.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: SCHED_RR && time_slice
Message-ID: <20111229171256.GA5955@redhat.com>
References: <1324584060.4222.15.camel@hp> <20111226165930.GA4075@redhat.com> <1325177015.9304.9.camel@hp>
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On 12/29, Kirill Tkhai wrote:
>
> Thanks for the answers, Oleg.
>
> On Mon, 2011-12-26 at 17:59 +0100, Oleg Nesterov wrote:
> > On 12/23, Kirill Tkhai wrote:
> > >
> > > RT class uses its own fixed
> > > timeslice (in case of RR),
> >
> > which looks confusing too, btw.
> >
> > sched_set_scheduler() does not initialize rt.time_slice, and
> > INIT_TASK() sets time_slice = HZ (not DEF_TIMESLICE).
> >
>
> I talk about task_tick_rt().

me too ;)

> When time_slice is over, it is being
> renewed. New value is DEF_TIMESLICE. This happens in case of SCHED_RR
> class.

Yes, but I was talking about initial value of time_slice, when the
task switches to SCHED_RR.

Oleg.