Date: Tue, 10 Nov 2015 11:34:38 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Juri Lelli <juri.lelli@gmail.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Eduardo Valentin <edubezval@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
        Arjan van de Ven <arjan@linux.intel.com>, Paul Turner <pjt@google.com>,
        Len Brown <len.brown@intel.com>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Andi Kleen <andi.kleen@intel.com>,
        Rafael Wysocki <rafael.j.wysocki@intel.com>
Subject: Re: [RFC PATCH 0/3] CFS idle injection
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On Tue, Nov 10, 2015 at 10:07:35AM +0000, Juri Lelli wrote:
> Do you think that using SCHED_DEADLINE here would be completely
> foolish? I mean, we would have the duty_cycle/period thing for free, it
> would be know to the scheduler (as to maybe address Thomas' concerns)
> and we could think to make idle injection part of system analysis (for
> the soft-RT use cases).

DEADLINE would be awesome, but I think we need work on two fronts before
we can really sell it as the awesome that it is ;-)

 - greedy and or statistical bounds
 - !priv

The first is such that we can better deal with the erratic nature of
media decode without going full worst case on it, and the second just
makes it so much more accessible.
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