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+====== Frequency scaling ======
+===== How to disable frequency scaling =====
+This guide explains an easy way to disable **frequency scaling**.
+First thing to do is to check the number of CPUs in the system with the command:
+<code bash>
+ls /sys/devices/system/cpu/
+</code>
+The provided output will be something like this:
+<code bash>
+cpu0  cpu2  cpuidle       kernel_max  modalias  online    power    uevent
+cpu1  cpu3  intel_pstate  microcode   offline   possible  present
+</code>
+and in this case the number of physical CPUs for which we can disable frequency scaling is four, namely ''cpu0'', ''cpu1'', ''cpu2'' and ''cpu3''.
+With the following script executed by with the //root// privilege:
+<code bash>
+ for i in $(seq 0 3) ; do echo "performance" > /sys/devices/system/cpu/cpu${i}/cpufreq/scaling_governor; done
+</code>
+we can set the ''performance'' governator policy, which disable frequency scaling. We used ''$(seq 0 3)'' because we have 4 CPUs, from ''cpu0'' to ''cpu3''. In a system with 8 physical cores, the correct command would have been ''$(seq 0 7)''. Remember that the script must be re-executed each time the system is restarted.
+To check that frequency scaling is effectively disabled, you can type many times the following command checking that the frequencies of your CPUs are fixed to the highest values:
+<code bash>
+cat /proc/cpuinfo
+</code>

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