Take any tests with scaling governor "powersave" using the intel_pstate with a grain of salt. This powersave mode has nothing in common with the acpi_cpufreq's

Take any tests with scaling governor "powersave" using the intel_pstate with a grain of salt. This powersave mode has nothing in common with the acpi_cpufreq's version of powersave and is quite aggressive at clocking down the CPU, even in periods of 100% CPU usage (when it decides that the throughput benefit of remaining highly clocked isn't worth it). This happens especially on memory-bound codes. See for example https://stackoverflow.com/a/45201673/149138 https://stackoverflow.com/a/45201673/149138 and https://stackoverflow.com/questions/43343231/enhanced-rep-movsb-for-memcpy https://stackoverflow.com/questions/43343231/enhanced-rep-mo... - both of which show large performance variance between powersave and performance. In the first example, the CPU clocks down indefinitely to 1.1 GHz from a nominal 2.6 GHz despite being 100% CPU-bound, and performance is cut in half. Despite having the same governor name, "powersave" with acpi-cpufreq has no relationship. It's using low-frequency software control and generally ramps up to 100% frequency (highest pstate) once CPU-bound code starts running and stays there.