AMD CPUs will be more efficient in Linux

P-State EPP driver for AMD hardware is being updated to improve the efficiency of the CPUs; will land in kernel 6.2.

CPUs evolved severely in the last couple of years, alongside GPUs; they both became much more intelligent to adjust their clock speeds while sitting idle or under heavy load. The old CPUs were sitting at 3 GHz even if you were simply looking at the screen, not even moving the mouse. With the changes in the algorithms, even the most powerful CPUs draw a little power when they “decide” it is time to lower the voltage.

Efficiency mode vs performance mode

The P-State EPP (Energy Performance Preference) drivers for AMD CPUs in Linux systems are updated. P-State is where the CPU is under load; the algorithms help the CPU to change its clock speeds depending on the temperature, while also trying to keep the power consumption as low as possible depending on the load. And now, with the changes in the P-State EPP driver, AMD CPUs can deliver better performance-per-watt.

Better efficiency in the P-State EPP drivers is achieved by implementing the use of ACPI CPPC EPP information as well. With this information, the CPU can decide to run in efficiency mode or performance mode, depending on the software it is currently running. Some early benchmarks confirm that the new driver indeed makes a difference in performance-per-watt.

The new driver is expected to be implemented in the Linux kernel 6.2 release. While the kernel 6.1 merge window is currently open, the driver is not ready to be merged yet.

by Rusen Gobel