ACPI CPUfreq vs. Intel P-State Scaling With Linux 3.15

Overall, these results were very interesting of the Intel P-State and ACPI CPUfreq drivers on the Linux 3.15 kernels. Among the findings:

- Intel P-State could still benefit from some additional tweaking with its performance still not matching ACPI CPUfreq when both were using the performance scaling governor in select workloads.

- With the above statement though, both P-State and ACPI CPUfreq with the performance governors generally delivered the best performance over the other scaling choices. Though if you're a gamer, it seemed ACPI CPUfreq performance was the slight favorite over P-State, at least for the Intel Core i7 4960X EE system. The performance governors also led to the best performance-per-Watt with the increased power usage / higher CPU power state generally being worth the performance gains.

- Those more concerned about power usage / battery life over performance should see how the Intel P-State powersave and ACPI CPUfreq conservative modes work out for their needs.

Coming up I'll see if the story is any different with the latest-generation Intel Haswell processors. If you appreciate this unique testing done at Phoronix, please subscribe to Phoronix Premium, consider a PayPal tip, or at the very least disable AdBlock when viewing these articles as they are extremely time and resource intensive. Thanks!