Date: Wed, 23 Dec 2009 10:52:39 +0100
From: Pavel Machek <pavel@ucw.cz>
To: Salman Qazi <sqazi@google.com>
Cc: linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org,
       Andrew Morton <akpm@linux-foundation.org>,
       Michael Rubin <mrubin@google.com>, Taliver Heath <taliver@google.com>,
       Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>
Subject: Re: RFC: A proposal for power capping through forced idle in the
 Linux Kernel
Message-ID: <20091223095239.GD24181@elf.ucw.cz>
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 <20091221085713.GA1622@ucw.cz>
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Hi!

> > OTOH realtime people already have tools you could make good use of:
> > your power capping approach looks like 'high priority idle task that
> > needs to run for 2 seconds every 5 seconds' or something...
> >
> > Talk to rt people?
> 
> At the core of it, you are correct.  However, in our implementation it
> also avoids running when the system is already idle and operates at
> much finer granularities than seconds.

Seconds were examples, I suspect rt kernels need lower granularities,
to.

> Which specific tools are you referring to?  Real-time Linux as a whole
> is a trade off:  one gets predictable latency in exchange for some
> performance.  Any specific contacts that I should direct my inquiries
> to?

I guess Peter and Ingo (added to the Cc)....

Anyway, I guess that what you really want is to be able to change
priority of the idle threads, even making them realtime...
									Pavel
-- 
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