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Subject: Re: NMI watchdog triggering during load_balance
From: Mike Galbraith <efault@gmx.de>
To: David Ahern <david.ahern@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
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Date: Fri, 06 Mar 2015 20:29:15 +0100
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On Fri, 2015-03-06 at 11:37 -0700, David Ahern wrote:

> But, I do not understand how the wrong topology is causing the NMI 
> watchdog to trigger. In the end there are still N domains, M groups per 
> domain and P cpus per group. Doesn't the balancing walk over all of them 
> irrespective of physical topology?

You have this size extra large CPU domain that you shouldn't have,
massive collisions therein ensue.

	-Mike