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Date: Wed, 4 May 2016 17:45:10 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Chris Mason <clm@fb.com>, Mike Galbraith <mgalbraith@suse.de>,
        Ingo Molnar <mingo@kernel.org>,
        Matt Fleming <matt@codeblueprint.co.uk>, linux-kernel@vger.kernel.org
Subject: Re: sched: tweak select_idle_sibling to look for idle threads
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On Tue, May 03, 2016 at 11:11:53AM -0400, Chris Mason wrote:
> # pick a single core, in my case cpus 0,20 are the same core
> # cpu_hog is any program that spins
> #
> taskset -c 20 cpu_hog &
> 
> # schbench -p 4 means message passing mode with 4 byte messages (like
> # pipe test), no sleeps, just bouncing as fast as it can.
> #
> # make the scheduler choose between the sibling of the hog and cpu 1
> #
> taskset -c 0,1 schbench -p 4 -m 1 -t 1

Will that schbench thingy print something? Mine doesn't seem to output
anything, not actually exit, although it stops consuming CPU cycles at
some point.