scaling_max_freq not applied correctly on charger→battery transition #924
Description
The issue I describe below happens with the intel_pstate driver. I am aware it is recommended in the README to use the acpi driver. Still, I thought it would still be useful to open the issue, as it might not be well known. If that's not the case just let me know and close the issue.
Have you tried?
- Searching through existing/closed issues to see if your bug has already been already submitted? yes, did not find e=any
- If installation failed with auto-cpufreq-installer,have you tried installing auto-cpufreq using Snap package? no, I use archlinux
- Have you tried configuring auto-cpufreq? yes, I share my config below
- Have you tried suggestions in troubleshooting section? yes, except changing the driver, which I would prefer to avoid
error
set_frequencies() in core.py caches the power supply state and only runs once per power transition. However, other operations in the same cycle (governor changes, turbo toggling, EPP/EPB writes, or maybe something else) can cause intel_pstate to recalculate and override scaling_max_freq after set_frequencies() has already run. Since the function skips all subsequent cycles (power supply unchanged), the frequency is never corrected.
Steps to reproduce
- My config file:
# settings for when connected to a power source
[charger]
# see available governors by running: cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
# preferred governor
governor = performance
# EPP: see available preferences by running: cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_available_preferences
energy_performance_preference = balance_performance
# minimum cpu frequency (in kHz)
# example: for 800 MHz = 800000 kHz --> scaling_min_freq = 800000
# see conversion info: https://www.rapidtables.com/convert/frequency/mhz-to-hz.html
# to use this feature, uncomment the following line and set the value accordingly
# scaling_min_freq = 800000
# maximum cpu frequency (in kHz)
# example: for 1GHz = 1000 MHz = 1000000 kHz -> scaling_max_freq = 1000000
# see conversion info: https://www.rapidtables.com/convert/frequency/mhz-to-hz.html
# to use this feature, uncomment the following line and set the value accordingly
# scaling_max_freq = 3300000
# turbo boost setting. possible values: always, auto, never
turbo = auto
# settings for when using battery power
[battery]
# see available governors by running: cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
# preferred governor
governor = powersave
# EPP: see available preferences by running: cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_available_preferences
energy_performance_preference = balance_power
# minimum cpu frequency (in kHz)
# example: for 800 MHz = 800000 kHz --> scaling_min_freq = 800000
# see conversion info: https://www.rapidtables.com/convert/frequency/mhz-to-hz.html
# to use this feature, uncomment the following line and set the value accordingly
# scaling_min_freq = 800000
# maximum cpu frequency (in kHz)
# see conversion info: https://www.rapidtables.com/convert/frequency/mhz-to-hz.html
# example: for 1GHz = 1000 MHz = 1000000 kHz -> scaling_max_freq = 1000000
# to use this feature, uncomment the following line and set the value accordingly
# scaling_max_freq = 1000000
# turbo boost setting (always, auto, or never)
turbo = auto
# battery charging threshold
# reference: https://github.com/AdnanHodzic/auto-cpufreq/#battery-charging-thresholds
#enable_thresholds = true
#start_threshold = 20
#stop_threshold = 80
- Run on an Intel CPU with intel_pstate driver (tested on i7-10510U)
- Plug in charger, wait a few seconds, then unplug charger
- Check:
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
Expected: 1800000, which is the standard value for this CPU
Actual: Value is lower (sometimes 936000, others 684000)
the max frequency stays capped, until I run:
sudo sh -c 'echo 1800000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq'
after which the problem remains solved (until the next power cycle).
System information (when the bug does not occur):
$ auto-cpufreq --debug
Using settings defined in /etc/auto-cpufreq.conf file
-------------------------------------------------------------------------------
Linux distro: Arch Linux rolling n/a
Linux kernel: 6.18.7-arch1-1
Processor: Intel(R) Core(TM) i7-10510U CPU @ 1.80GHz
Cores: 8
Architecture: x86_64
Driver: intel_pstate
------------------------------ Current CPU stats ------------------------------
CPU max frequency: 1800 MHz
CPU min frequency: 400 MHz
Core Usage Temperature Frequency
CPU0 8.1% 44 °C 1800 MHz
CPU1 3.1% 46 °C 1800 MHz
CPU2 3.0% 44 °C 1800 MHz
CPU3 9.2% 45 °C 1800 MHz
CPU4 6.1% 44 °C 1800 MHz
CPU5 4.0% 46 °C 1800 MHz
CPU6 3.0% 44 °C 1800 MHz
CPU7 26.5% 45 °C 1800 MHz
CPU fan speed: 5028 RPM
CPU fan speed: 5028 RPM
auto-cpufreq version: Version : 3.0.0-3
Python: 3.14.2
psutil package: 7.2.1
platform package: 1.0.9
click package: 8.3.1
distro package: 1.9.0
Computer type: Notebook
Battery is: charging
auto-cpufreq system resource consumption:
cpu usage: 0.0 %
memory use: 0.38 %
Total CPU usage: 6.5 %
Total system load: 1.11
Average temp. of all cores: 45.00 °C
Currently using: performance governor
Currently turbo boost is: off
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