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Message-ID: <1453829961.3534.36.camel@gmail.com>
Subject: Re: fast path cycle muncher (vmstat: make vmstat_updater deferrable
 again and shut down on idle)
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Christoph Lameter <cl@linux.com>
Cc: Michal Hocko <mhocko@kernel.org>, Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>
Date: Tue, 26 Jan 2016 18:39:21 +0100
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On Tue, 2016-01-26 at 10:26 -0600, Christoph Lameter wrote:
> On Tue, 26 Jan 2016, Mike Galbraith wrote:
> 
> > On Tue, 2016-01-26 at 03:14 +0100, Mike Galbraith wrote:
> > 
> > > Perf and RT say we don't want quiet_vmstat() in the idle loop
> > > either.
> > 
> > BTW, the perf numbers were not from an RT kernel, they were from my
> > PREEMPT_VOLUNTARY desktop kernel.
> 
> Can we move quiet_vmstat() elsewhere after we have checked that really
> nothing else is going on soon?

How would you check?  Precognition doesn't work for mortals.

	-Mike