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Date: Fri, 12 Aug 2016 16:26:13 +0200
From: Frederic Weisbecker <fweisbec@gmail.com>
To: Christoph Lameter <cl@linux.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Chris Metcalf <cmetcalf@mellanox.com>,
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        Daniel Lezcano <daniel.lezcano@linaro.org>, linux-doc@vger.kernel.org,
        linux-api@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: clocksource_watchdog causing scheduling of timers every second
 (was [v13] support "task_isolation" mode)
Message-ID: <20160812142611.GC5087@lerouge>
References: <alpine.DEB.2.20.1607212118210.12213@east.gentwo.org>
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On Fri, Aug 12, 2016 at 09:23:13AM -0500, Christoph Lameter wrote:
> On Thu, 11 Aug 2016, Paul E. McKenney wrote:
> 
> > Heh!  The only really good idea is for clocks to be reliably in sync.
> >
> > But if they go out of sync, what do you want to do instead?
> 
> For a NOHZ task? Write a message to the syslog and reenable tick.

Indeed, a strong clocksource is a requirement for a full tickless machine.