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Date: Sun, 13 Nov 2016 12:53:28 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
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To: Peter Zijlstra <peterz@infradead.org>
cc: Daniel Vacek <neelx.g@gmail.com>,
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Subject: Re: [PATCH] sched/rt: RT_RUNTIME_GREED sched feature
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On Fri, 11 Nov 2016, Peter Zijlstra wrote:

> On Fri, Nov 11, 2016 at 12:46:37PM -0600, Christoph Lameter wrote:
> > On Thu, 10 Nov 2016, Daniel Vacek wrote:
> >
> > > I believe Daniel's patches are the best thing we can do in current
> > > situation as the behavior now seems rather buggy and does not provide above
> > > mentioned expectations set when rt throttling was merged with default
> > > budget of 95% of CPU time. Nor if you configure so that it does (by
> > > disabling RT_RUNTIME_SHARE), it also forces CPUs to go idle needlessly when
> > > there still can be rt task running not really starving anyone. At least
> > > till a proper rework of rt scheduling with DL Server is implemented.
> >
> > This looks like a fix for a bug and the company I work for is suffering
> > as a result. Could we please merge that ASAP?
> >
>
> What bug? And no, the patch has as many technical issues as it has
> conceptual ones.

There is a deadlock, Peter!!!