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Subject: Re: [ANNOUNCE] 3.8-rc6-nohz4
From: Steven Rostedt <rostedt@goodmis.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        Alessio Igor Bogani <abogani@kernel.org>,
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        Paul Gortmaker <paul.gortmaker@windriver.com>,
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        Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 07 Feb 2013 12:03:47 -0500
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On Thu, 2013-02-07 at 17:45 +0100, Frederic Weisbecker wrote:

> >
> > config NO_HZ_TASK
> >         bool "Stop tick on specified CPUs when single task is running"
> >         default n
> >         depends on NO_HZ
> 
> Ok I launched another debate about that single task thing. I wish we
> don't make it a fundamental component but rather an implementation
> detail that can be dynamically dealt with in the future.

It's not just an implementation detail, as it is very visible to the
user. If they want to take advantage of a task NO_HZ they have to go
through a bit of loops to make sure only a single task is running on a
CPU. We should be broadcasting this requirement to educate the users on
exactly how they can take advantage of this feature.


>  Anyway let's
> talk about that on my previous answer.

I already did ;-)

-- Steve