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Date: Mon, 30 Jul 2007 18:25:12 -0700
From: Nate Lawson <nate@root.org>
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To: Hajimu UMEMOTO <ume@freebsd.org>
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Cc: acpi@freebsd.org, freebsd-hackers@freebsd.org,
	Pietro Cerutti <gahr@gahr.ch>
Subject: Re: [patch] enhance powerd(8) to handle max temperature
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Hajimu UMEMOTO wrote:
>>>>>> On Mon, 30 Jul 2007 23:31:33 +0200
>>>>>> Pietro Cerutti <gahr@gahr.ch> said:
> gahr> My patch is really just a first draft that I wrote in order to have
> gahr> feedbacks on the general idea to implement a temperature controlling
> gahr> system inside powerd, and doesn't implement hysteresis as you noted, and
> gahr> your feedback is that it's not a good idea, which I respect.
> 
> It is rather backward, IMHO.  I did implement a passive cooling
> feature as an enhancement of powerd(8) like you did, during initial
> phases.  Then, I implemented it in our kernel as a result.

I'll take a look at your patch.  Umemoto-san is right in that you really
want the kernel to control cooling.  What happens if powerd dies/hangs
and your system burns up?  Passive cooling is often a last resort to
keep the system from overheating.

-Nate