Re: v4.8-rc1: thinkpad x60: running at low frequency even during kernel build

From: Pandruvada, Srinivas
Date: Fri Nov 04 2016 - 17:13:06 EST


On Fri, 2016-11-04 at 21:44 +0100, Pavel Machek wrote:
> Hi!
>
> >
> > >
> > > Let me try v4.9-rc2... that works ok (cpus at the high frequency
> > > during the kernel build). Unfortunately that sends my cpus to 99C
> > > temperature range (and eventually forces emergency shutdown).
> >
> > This we have to debug. Do you see same line likeÂ
> > "
> > /sys/devices/system/cpu/cpu0/cpufreq/bios_limit:1000000
> > "
> > If not we need
> > to find out why.
>
> I'd prefer mails over bugzilla for now...
>
> 4.9-rc2 has bios_limit:
>
> pavel@duo:~$ cat /sys/devices/system/cpu/cpu0/cpufreq/bios_limit
> 1833000
>
> and it has thermal zones:
>
> /sys/devices/virtual/thermal/thermal_zone0/trip_point_0_temp 127000
> /sys/devices/virtual/thermal/thermal_zone0/trip_point_0_type critical
> /sys/devices/virtual/thermal/thermal_zone1/trip_point_0_temp 97000
> /sys/devices/virtual/thermal/thermal_zone1/trip_point_0_type critical
> /sys/devices/virtual/thermal/thermal_zone1/trip_point_1_temp 92500
> /sys/devices/virtual/thermal/thermal_zone1/trip_point_1_type passive
>
It will not act if there is no binding information. Do you have more
files in this folder?

grep -r . * in /sys/class/thermal will be helpful.


> ..so it should slow down CPU at 92C.
>
> So lets push the temperature up a bit...
>
> sudo watch cat /proc/acpi/ibm/thermal
> /sys/devices/system/cpu/cpu0/cpufreq/bios_limit
> /sys/devices/virtual/thermal/thermal_zone1/tempÂÂ/sys/devices/system/
> cpu/cpu0/cpufreq/cpuinfo_cur_freq
>
> temperatures:ÂÂÂ98 49 -128 85 28 -128 28 -128 49 58 -128 -128 -128
> -128 -128 -128
> 1833000
> 95000
> 1833000
>
> Hmm. bios_limit does not seem to change, even when the temperature is
> clearly above the trip point. (It is also interestng that acpi/ibm
> reports bigger temperatures than
> /sys/devices/virtual/thermal/thermal_zone1/temp . I have seen 103C
> there.)
Probably they are showing package and core temperature or have a
different sampling interval.

Try enabling thermald service in Debian. it has access to more knobs to
control thermals.

Thanks,
Srinivas