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Date: Fri, 11 Nov 2016 23:53:28 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Lameter <cl@linux.com>
Cc: Daniel Vacek <neelx.g@gmail.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
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        Steven Rostedt <rostedt@goodmis.org>, Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH] sched/rt: RT_RUNTIME_GREED sched feature
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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.