Re: [PATCH] watchdog: nohz: don't run watchdog on nohz_full cores

[Chris Metcalf]

On 03/30/2015 10:04 PM, Mike Galbraith wrote:
> On Mon, Mar 30, 2015 at 02:51:05PM -0400, cmetcalf@xxxxxxxxxx wrote:
> > From: Chris Metcalf <cmetcalf@xxxxxxxxxx>
> >
> > Running watchdog can be a helpful debugging feature on regular
> > cores, but it's incompatible with nohz_full, since it forces
> > regular scheduling events.  Accordingly, just exit out immediately
> > from any nohz_full core.
> Hm, I don't see why this is needed, for debugging/testing you turn it
> on, when you set up for critical operation, you turn it off.

It can be helpful to keep the watchdog running even in production
to help diagnose hard-to-reproduce failures.  You just can't have it
running on the nohz_full cores.

--
Chris Metcalf, EZChip Semiconductor
http://www.ezchip.com

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