Fan+heat troubles on MacBook Pro

[Steven Noonan]

On Mon, Nov 29, 2010 at 2:18 AM, christoffer.buchholz at gmail.com
<christoffer.buchholz at gmail.com> wrote:
> Thank you for your quick reply!
> To answer you questions...
>
> 1) uname -a reads "Linux gomet 2.6.35.6-48.fc14.x86_64" - I have also tried
> with the kernel from the bleeding edge fedora 15 repo, but that didnt change
> much if anything at all.

Alright, so the stock Fedora kernel, then.

> 2) According to apple documentation, my processor is a "2.53GHz Intel Core 2
> Duo processor with 3MB on-chip shared L2 cache running 1:1 with processor
> speed" and has a "1066MHz frontside bus" <- I guess that is the rated clock
> frequency.

2.53 GHz is the rated clock frequency. :)

> 3) 'cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor' reads
> "ondemand"

Good, so it should be scaling...

> 4) 'cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq' reads
> "798000" and it does that even when i shut down all apps running, so it
> seems its actually not so ondemand

And it is scaling down properly. 798MHz is as low as SpeedStep allows
that processor to go.

> 5) I'm not very technical, so but here's some of the stuff, which I guess is
> the important part, from powertop. It doesnt really change more than a few
> numbers up and down, so it should be good: http://fpaste.org/7G9b/

Looks like it's staying clocked down to 798MHz just fine, so there's
no way that cpufreq is screwing up.

> 6) The output from /proc/interrupts doesnt seem to change that much. You can
> see the output from '/proc/interrupts; sleep 0.5s; cat /proc/interrupts'
> here http://fpaste.org/QXVO/

Okay, it looks like interrupts are being handled properly. Nothing
there jumps out as abnormal.

Rereading your original post, I think I was an idiot and missed
something that I shouldn't have... You mention that the "fan is not
functioning properly". Is this a hardware thing you're trying to work
around, or are the fans just not spinning up when the machine gets
warm? If you don't mind a performance impact, you could change the
scaling governor to 'powersave', and the CPU won't automatically clock
up under load. Alternatively, you could probably set the minimum fan
speeds to a higher level (they're probably at 2000 RPM by default, so
you may want to try 4000). Do this:

ls /sys/devices/platform/applesmc.*/fan*_min

It will probably list a couple different fans there, and you can 'cat'
them to see what the minimum is currently set to, or you can do
something like:

echo 4000 > /sys/devices/platform/applesmc.X/fanY_min

(obviously, replacing X and Y in the above with whatever the actual
values are from the above 'ls' output)

I haven't looked at my mid 2010 MacBook Pro's applesmc folder, but on
my 2007 MacBook Pro, there are fan1_min and fan2_min. They can be set
independently, so if you want one at 2000RPM and the other at 6000RPM,
there's nothing to prevent you from doing so. You probably will want
them to both be at the same speed, though.