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Date: Thu, 28 Jan 2016 16:36:46 +0100
From: Frederic Weisbecker <fweisbec@gmail.com>
To: Christoph Lameter <cl@linux.com>
Cc: Michal Hocko <mhocko@kernel.org>,
        Mike Galbraith <umgwanakikbuti@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: fast path cycle muncher (vmstat: make vmstat_updater deferrable
 again and shut down on idle)
Message-ID: <20160128153644.GA25866@lerouge>
References: <20160125174224.GH23934@dhcp22.suse.cz>
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 <1453833078.3534.59.camel@gmail.com>
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On Wed, Jan 27, 2016 at 10:28:48AM -0600, Christoph Lameter wrote:
> On Wed, 27 Jan 2016, Mike Galbraith wrote:
> 
> > > Since we (the NOHZ people) care mostly about NOHZ then lets restrict
> > > that to the NOHZ mode. Then it should not affect your load.
> >
> > Tons of folks do have NO_HZ enabled (including me).  Isn't there a spot
> > somewhere in NO_HZ_FULL code where it can take up residence?  (one with
> > a tad lower maximum call frequency would be good, a nohz_full cpu isn't
> > necessarily being used for pure compute exclusively)
> 
> Frederic, any idea on where to put quiet_vmstat()?

I guess those who want this also want task isolation, right? And Chris integrates
it in his patchset.