[ltp] Kick up the Fan - R50e Fan problems - Broken governors

Thomas Renninger linux-thinkpad@linux-thinkpad.org
Sun, 21 Aug 2005 19:05:13 +0200


Sorry for cross-posting, but this should be quite interessting for the
debian-laptop list as well.

David A. Desrosiers wrote:
> 
>> For now people with critical shutdown problems should go for the
>> userspace governor and a cpufreq daemon. There the max frequency is
>> lowered until the temperature sub-ceeds the passive trip point again.
>> That should work well.
> 
>     ...except on my T42p, apparently. I'm at 600Mhz most of the time and
> I can get the machine from a cold 48C bootup to >80C in about 10
> minutes, which results in a hard-lockup. Just play bzflag on it for 8-10
> minutes in full-screen mode, and it will rise over 40C in a very very
> short period of time.
Have you tried the suggested "DynamicClocks" "on" in Xorg.conf flag?
Here another report:
________________
Ok, I tried now Option "DynamicClocks" "on".

Where there is no significant change when the system is idle it seems that
applications with high graphics activity no longer trigger the alert.
________________
> 
>     I've been investigating some alternative cooling solutions to try to
> keep it down. I may create/repurpose a watercooler system for the GPU if
> I can't find a fan that will work in the tight confines of my laptop case.
> 
>> I will send a patch to be able to set the fan to full-speed seperately
>> (you gain some more time you can use the laptop on highest frequency).
> 
>     I wish the fan would run higher, actually. I've got it set to run
> from 40C to 75C, and it doesn't seem to make any difference. It just
> isn't moving enough of that hot air off of the GPU and CPU.
> 
>     Incidentally, I use the conservative governor. In my tests, it gives
> me 40-60 minutes more battery life than the powersave or userspace
> governors.
?!?
You probably won't gain more than the powersave governor as it always let
your frequncy stay at lowest speed.

The ondemand governor is tunable /sys/devices/system/cpu/cpu0/cpufreq/ondemand/up_threshold
(CPU load limit to go up, default is 20, more reasonable I think is 80).
But you are right the ondemand is designed for server purposes not losing any
performance.

(paste from another mail - too lazy to retype):
__________________________________________
However, when passive cooling works well, people shouldn't notice much.
It seems as if these machines are designed to work with OS thermal management.
The userspace governor works nicely and temperature stays at passive trip point
with 1200 instead of 1700 MHz (even on 70 C passive tp limit it stays at 1200 MHz
poking around 70 C - default is 92 C).

The ondemand govenor and I also expect the conservative governor do not consider
thermal limits yet, but this should be fixed soon and those critcal alert reports
will disappear.
__________________________________________


So you better go for a userspace governor for now, it will probably take some days/weeks until fixes
go mainline and it will take some weeks/months until it will pop up in any distribution.

Userspace governors depend on their implementation and configuration. The powersave package on sourceforge (not governor)
works well and I doubt you will see any difference to the conservative governor in respect of
performance and power consumption.

(Be careful, surreptitious advertising :) ):
--------------------------
As mentioned it's running on SUSE since about 2 years and got a lot workarounds (like trip points settings, suspend hooks,
 and much more). Be careful, when I played around with those Thinkpads, I realised that setting trip points is broken in current
CVS, I'll fix that on Monday.
Unfortunately there are not a lot packages flying around yet.
One guy built up packages for ALT Linux. Seems as it uses apt for packaging?
__________________
All rpm packages available from ALT Linux Sisyphus (apt-get repository):

ftp://ftp.altlinux.ru/pub/distributions/ALTLinux/Sisyphus/files/SRPMS/kpowersave-0.4.5-alt1.src.rpm
ftp://ftp.altlinux.ru/pub/distributions/ALTLinux/Sisyphus/files/SRPMS/powersave-0.9.25-alt2.src.rpm

also, powersave required for build rpm macros from fillup:
ftp://ftp.altlinux.ru/pub/distributions/ALTLinux/Sisyphus/files/SRPMS/fillup-1.42-alt3.src.rpm

and will be included to next release ALT Linux 3.0 (currently
Sisyphus-branch-3.0)
___________________

If anyone is so kind to build a apt/rpm package for any distribution, be sure that
reasonable patches/build scripts/etc will be included into the CVS thankfully.

You should also know that current head uses DBus to communicate and Hal to read some HW info.
If you don't like that dependency go for the SUSE_LINUX_9_3 branch.

     Thomas