[patch] enhance powerd(8) to handle max temperature

[Garrett Cooper]

M. Warner Losh wrote:
> In message: <46B15166.1070305 at elischer.org>
>             Julian Elischer <julian at elischer.org> writes:
> : Garrett Cooper wrote:
> : > M. Warner Losh wrote:
> : >> In message: <46AE8F78.1060203 at root.org>
> : >>             Nate Lawson <nate at root.org> writes:
> : >> : Hajimu UMEMOTO wrote:
> : >> : >>>>>> On Mon, 30 Jul 2007 23:31:33 +0200
> : >> : >>>>>> Pietro Cerutti <gahr at 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.
> : >>
> : >> I keep getting the system shutting down on my HP by FreeBSD because
> : >> the temperature exceeds the _CRT value.  Maybe there's something wrong
> : >> with my values, since it happens a lot:
> : >>
> : >> hw.acpi.thermal.min_runtime: 0
> : >> hw.acpi.thermal.polling_rate: 10
> : >> hw.acpi.thermal.user_override: 0
> : >> hw.acpi.thermal.tz0.temperature: 0.0C
> : >> hw.acpi.thermal.tz0.active: -1
> : >> hw.acpi.thermal.tz0.passive_cooling: 1
> : >> hw.acpi.thermal.tz0.thermal_flags: 0
> : >> hw.acpi.thermal.tz0._PSV: 90.0C
> : >> hw.acpi.thermal.tz0._HOT: -1
> : >> hw.acpi.thermal.tz0._CRT: 94.0C
> : >> hw.acpi.thermal.tz0._ACx: 40.0C -1 -1 -1 -1 -1 -1 -1 -1 -1
> : >>
> : >> Note: temperature is always 0.0C.
> : >>
> : >> What can I do to help my situation, if I really want the kernel doing
> : >> the cooling?
> : >>
> : >> Warner
> : >>   
> : > 
> : > Wow, something's really wrong with those calculated temperatures. At 
> : > that value most of the plastic and weaker circuitry should have fused 
> : > together =\.
> : 
> : It would be interesting to see what the values are just after booting,
> : or even earlier if you can get the bios to give temperatures 
> : (some MBs have that possibility)
>
> The values are always the same.  ACx is always 40C -1 ... and
> temperature is always 0.
>
> Warner
>   

    Not all temperature sensors report accurate values, just like fans' 
rpm levels.
-Garrett