Date: Mon, 17 Oct 2016 12:52:50 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Luca Abeni <luca.abeni@unitn.it>
Cc: linux-kernel@vger.kernel.org,
        Tommaso Cucinotta <tommaso.cucinotta@sssup.it>,
        Juri Lelli <juri.lelli@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andrea Parri <parri.andrea@gmail.com>,
        giuseppe lipari <giuseppe.lipari@lsv.ens-cachan.fr>,
        Claudio Scordino <claudio@evidence.eu.com>
Subject: Re: About group scheduling for SCHED_DEADLINE
Message-ID: <20161017105250.GP3117@twins.programming.kicks-ass.net>
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 <20161016213420.64b772da@utopia>
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On Sun, Oct 16, 2016 at 09:34:20PM +0200, Luca Abeni wrote:
> Hi Peter,
> 
> first of all, sorry for the delay in my answer

Not a problem, we're all busy. As it happens I had this thing in Berlin
which delayed me reading email in any case ;-)


> > However, I think there's a third alternative. I have memories of a
> > paper from UNC (I'd have to dig through the site to see if I can
> > still find it) where they argue that for a hierarchical (G-)FIFO you
> > should use minimal concurrency, that is run the minimal number of
> > (v)cpu servers.

> Ok, I need to find and read that paper

I had a real quick look and it could be this one, but memories are
vague...

  https://cs.unc.edu/~anderson/papers/ecrts08c.pdf

In particular 3.P.