Testing For The Latest Linux Kernel Power Regression

The change in power consumption for LAME MP3 encoding could technically be Intel FBC related since the screen rarely changes while the Phoronix Test Suite runs the MP3 encoding test, but when looking at the raw MP3 encoding performance there's a difference:

LAME consumed more power on Linux 3.16 and 3.17 kernels, but its performance was also noticeably faster. This is likely due to a change in the Intel P-State driver rather than being related to the potential FBC issue.

Lastly, for the system when idling for three minutes, the power consumption of this Ivy Bridge mobile system was basically the same across the five Linux kernels benchmarked.

You can explore the raw Ivy Bridge ultrabook power consumption data via this OpenBenchmarking.org result file.

Next up I tested an Intel Core i7 Haswell system looking for performance differences...