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Date: Wed, 21 Mar 2012 09:50:27 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
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To: Frederic Weisbecker <fweisbec@gmail.com>
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        Alessio Igor Bogani <abogani@kernel.org>,
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        Sven-Thorsten Dietrich <thebigcorporation@gmail.com>,
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Subject: Re: [PATCH 07/32] cpuset: Set up interface for nohz flag
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On Wed, 21 Mar 2012, Frederic Weisbecker wrote:

> Prepare the interface to implement the nohz cpuset flag.
> This flag, once set, will tell the system to try to
> shutdown the periodic timer tick when possible.
>
> We use here a per cpu refcounter. As long as a CPU
> is contained into at least one cpuset that has the
> nohz flag set, it is part of the set of CPUs that
> run into adaptive nohz mode.

What are the drawbacks for nohz?

If there are none: Can we make nohz default behavior without relying on
cpusets?