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Subject: Re: [PATCH RFC/RFT] sched/fair: Improve the behavior of sync flag
From: Mike Galbraith <efault@gmx.de>
To: Joel Fernandes <joelaf@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Josef Bacik <jbacik@fb.com>,
        Juri Lelli <Juri.Lelli@arm.com>,
        Brendan Jackman <brendan.jackman@arm.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Matt Fleming <matt@codeblueprint.co.uk>,
        Rik van Riel <riel@redhat.com>, Ingo Molnar <mingo@redhat.com>
Date: Sun, 27 Aug 2017 20:07:57 +0200
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On Sat, 2017-08-26 at 23:39 -0700, Joel Fernandes wrote:
> 
> Also about real world benchmarks, in Android we have usecases that
> show that the graphics performance and we have risk of frame drops if
> we don't use the sync flag so this is a real world need.

That likely has everything to do with cpufreq not realizing that your
CPUs really are quite busy when scheduling cross core at fairly high
frequency, and not clocking up properly.

	-Mike