# acpid temperature regulation confusion

## jonaswidarsson

dmesg | grep ACPI *Quote:*   

>  BIOS-e820: 000000000dff0000 - 000000000dff3000 (ACPI NVS)
> 
>  BIOS-e820: 000000000dff3000 - 000000000e000000 (ACPI data)
> 
> ACPI: RSDP (v000 KM400                                     ) @ 0x000f7260
> ...

 cat /proc/acpi/thermal_zone/THRM/polling_frequency

```
<polling disabled>

```

cat /proc/acpi/thermal_zone/THRM/temperature

```
temperature:            36C

```

rc-status default

```
Runlevel: default

  sshd                                                              [ started ]

  distccd                                                           [ started ]

  acpid                                                             [ started ]

  local                                                             [ started ]

  vixie-cron                                                        [ started ]

  syslog-ng                                                         [ started ]

  domainname                                                        [ started ]

  net.eth0                                                          [ started ]

  rsyncd                                                            [ started ]

  netmount                                                          [ started ]

  numlock                                                           [ started ]

```

I wonder how I can be sure that acpid controls the fan speed to protect the cpu?

If I read the man page it just says it can be configured to read events and run some scripts. Isn't this part of the kernel supposed to take care of cpu temp automatically by default?

----------

## MaGuS

No one knows about this?

Best regards,

Magnus

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## li1_getoo

what kernel you using

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## jonaswidarsson

I am using gentoo-dev-sources 2.6.1-rc1 (I'm not 100% sure on that rc).

I get no errors, I just wonder if everything is the way things should be?

I was fiddling with this on another computer earlier in january, and thought I had to write a cron script to run "acpi -t" every minute, cause then I can really hear the difference.

But that can't be it?

Maybe I can change the <polling_disabled> to something else and get this to a trustworthy impression. Right now I don't really know if the kernel does what it should.

One big question:

Why isn't this completely hardware controlled in the first place?

It is stupid to depend on software to change the speed of the cpu fan.

OK, I don't have a distinct problem. The problem is that I don't know if I have a problem or not.

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## MaGuS

I am using 2.6.3-gentoo-r1.

Magnus

----------

## mirekm

I had problem with buggy DSDT, and there was also 

<Polling disabled> so the temperature was net checked by the system. I worked aoround of this problew with just

cat -n 5 > /proc/acpi/thermal_zone/THM0/polling_frequency

Than system checked the state of thermal zone every 5 seconds.

Now I have corrected DSDT and it works fine.

Regards

----------

## MaGuS

What is DSDT ?   :Shocked: 

Magnus

----------

## jonaswidarsson

 *mirekm wrote:*   

> cat -n 5 > /proc/acpi/thermal_zone/THM0/polling_frequency

 

Thankyouuuu,  thankyou Lauraaaaaa, thankyoouuuuuu,  thankYOUUUUUU!

Does that mean that it'll work even after reboot or will I have to issue that command again at startup? 

I'll read up on DSDT.

----------

