AMD Rembrandt CPUFreq vs. AMD P-State Linux Testing

AMD P-State with the scheduler utilization "Schedutil" governor is the common AMD default on modern Linux distributions... Unfortunately, it was often yielding the worst performance as shown in the browser benchmarks. Using schedutil performed much more poorly than even acpi-cpufreq ondemand as the former common default prior to the amd-pstate introduction or Schedutil gaining popularity.

When looking at the CPU peak frequency being obtained as the highest for any of the cores, the amd-pstate schedutil configuration on average was peaking about 3.3GHz compared to acpi-cpufreq schedutil and acpi-cpufreq ondemand hitting around 3.6GHz on average or the acpu-cpufreq performance governor with a 4.19GHz peak average and the amd-pstate performance mode up at 4.7GHz.

Obviously the amd-pstate schedutil clocking lower led to a lower SoC temperature during this benchmark, but it was just a few degrees lower.

Interestingly when looking at the battery power consumption during this Chrome browser benchmark, the schedutil and ondemand configurations were drawing an average of 13.6 Watts while amd-pstate performance was at 13.9 Watts with its leading performance. The acpi-cpufreq performance configuration had the highest average power consumption at 15.2 Watts.

Jetstream 2 is one of the most demanding web browser benchmarks at the moment. Again, here the default amd-pstate schedutil configuration on Ubuntu led to the worst performance....

The amd-pstate schedutil was sticking to much lower clocks than even acpi-cpufreq schedutil or acpi-cpufreq ondemand.

At least amd-pstate schedutil is nice for making a cool laptop....

But with the battery power consumption results, the amd-pstate performance and acpi-cpufreq performance modes were actually delivering the best performance-per-Watt.

AMD-pstate schedutil was consistently in last place for performance among the web browser benchmarks.