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Message-ID: <1421827607.5772.19.camel@marge.simpson.net>
Subject: Re: [LKP] [rcu] 00f5159aeb6: +55.3%
 will-it-scale.time.involuntary_context_switches
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: paulmck@linux.vnet.ibm.com
Cc: Huang Ying <ying.huang@intel.com>, LKML <linux-kernel@vger.kernel.org>,
        LKP ML <lkp@01.org>
Date: Wed, 21 Jan 2015 09:06:47 +0100
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On Tue, 2015-01-20 at 23:52 -0800, Paul E. McKenney wrote: 
> On Wed, Jan 21, 2015 at 03:32:44PM +0800, Huang Ying wrote:
> > FYI, we noticed the below changes on
> > 
> > git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git stall.2015.01.06a
> > commit 00f5159aeb68f08ce29597be86be87d6db0c1ba1 ("rcu: Run grace-period kthreads at real-time priority")
> 
> Glad this helps!

The way I read it, it's hurting by increasing context switches... but if
you'll need a boot param to turn it on in the future, this is moot :)

-Mike