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Date:   Thu, 7 Sep 2023 14:33:49 +0100
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Subject: Re: [RFC PATCH 0/7] sched: cpufreq: Remove magic margins
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To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Qais Yousef <qyousef@layalina.io>, linux-kernel@vger.kernel.org,
        linux-pm@vger.kernel.org, "Rafael J. Wysocki" <rafael@kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
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        Vincent Guittot <vincent.guittot@linaro.org>,
        Viresh Kumar <viresh.kumar@linaro.org>
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From:   Lukasz Luba <lukasz.luba@arm.com>
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On 9/7/23 14:29, Peter Zijlstra wrote:
> On Thu, Sep 07, 2023 at 02:06:15PM +0100, Lukasz Luba wrote:
> 
>>> Many extentions to the periodic task model are possible, including
>>> things like average runtime with bursts etc.. all have their trade-offs.
>>
>> Was that maybe proposed somewhere on LKML (the other models)?
> 
> RT literatur mostly methinks. Replacing WCET with a statistical model of
> sorts is not uncommon, the argument goes that not everybody will have
> their worst case at the same time and lows and highs can commonly cancel
> out and this way we can cram a little more on the system.
> 
> Typically this is proposed in the context of soft-realtime systems.

Thanks Peter, I will dive into some books...