how to make cpugovernor intel_pstate stable?
It is not possible for your processor to always be at your max turbo rate of 3200MHz all the time. If you have many cores active at once, then the max frequency will be only 2.6Ghz, and that limit is fundamental within the processor itself (see also your i7z screenshot - Max Turbo Multiplier line). However you can easily pretty much have all CPUs always at 2.6 GHz by setting the min and max percent numbers accordingly. However, note that you will still observe sometimes less frequency, as the processor can back off by itself under very low load conditions. Even easier would be to set turbo to off and performance mode, effectively makes all CPU run at 2.4 GHz all the time (but again, the processor itself can back off under extremely low load).
Example for setting 2.6Ghz (if I did my math properly):
echo "81" | sudo tee /sys/devices/system/cpu/intel_pstate/max_perf_pct
echo "81" | sudo tee /sys/devices/system/cpu/intel_pstate/min_perf_pct
Example for the non-turbo method:
echo "1" | sudo tee /sys/devices/system/cpu/intel_pstate/no_turbo
$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
powersave
powersave
powersave
powersave
powersave
powersave
powersave
powersave
$ sudo su
# for file in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do echo "performance" > $file; done
# exit
exit
$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
performance
performance
performance
performance
performance
performance
performance
performance
There is a command line tool for that called pstate-frequency.
To install it, simply follow the instructions in the repository.
What the script does is that it allows you to tell your CPU your preferred settings regarding clock speed, governor and turbo boost.
But keep in mind, since newer Intel CPU's are highly optimized and do power management on their own you cannot force your CPU, rather suggest what you want.
See this from the description of pstate-frequency:
For contemporary Intel processors, the frequency is controlled by the processor itself and the P-states exposed to software are related to performance levels. The idea that frequency can be set to a single frequency is fiction for Intel Core processors. Even if the scaling driver selects a single P state the actual frequency the processor will run at is selected by the processor itself.
To get the highest possible clock speed (permanently 3.2 GHz (ideally)) and the performance governor execute this after installing the script:
sudo pstate-frequency --color -S -p 3
You can use pstate-frequency -G --color to get your currently set power plan.
For me using a intel i7-4790K I get permanently 4400 MHz with all cores.
To check your current CPU clock you can use:
watch -n 0,3 'cat /proc/cpuinfo | grep "MHz"'
This will list the clock speed of all your CPU threads.
In my case after setting power plan '3' ([...] -p 3) (performance) I get:
cpu MHz : 4399.843
cpu MHz : 4400.156
cpu MHz : 4391.093
cpu MHz : 4400.000
cpu MHz : 4400.000
cpu MHz : 4400.468
cpu MHz : 4400.156
cpu MHz : 4361.718