From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl@linux.com>
Subject: Re: clocksource_watchdog causing scheduling of timers every second
 (was [v13] support "task_isolation" mode)
Date: Thu, 11 Aug 2016 18:02:34 -0500 (CDT)
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To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
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On Thu, 11 Aug 2016, Paul E. McKenney wrote:

> > With modern Intel we could run it on one CPU per package I think, but at
> > the same time, too much in NOHZ_FULL assumes the TSC is indeed sane so
> > it doesn't make sense to me to keep the watchdog running, when it
> > triggers it would also have to kill all NOHZ_FULL stuff, which would
> > probably bring the entire machine down..
>
> Well, you -could- force a very low priority CPU-bound task to run on
> all nohz_full CPUs.  Not necessarily a good idea, but a relatively
> non-intrusive response to that particular error condition.

Given that we want the cpu only to run the user task I would think that is
not a good idea.