Since last year when spotting a major Linux kernel power regression and subsequently finding the cause of the power problem that affected a large number of mobile Linux users, plus other regressions, it's been fun to look at the Linux power performance situation. How though is the latest Ubuntu Linux code performing when it comes to power efficiency? Here are some early tests of Ubuntu 12.10.
Overall, the latest upstream Linux code that is found in Ubuntu 12.10 appears to be in fairly good shape. Most of the Linux power issues have been resolved, although there are a few other regressions I have spotted that I am currently looking into and will then publish. In this article are some new Ubuntu power consumption results from Ubuntu 11.04, 11.10, 12.04 LTS, and 12.10 2012-06-26 from an Intel Sandy Bridge Extreme system.
The results illustrated in this article are roughly equivalent to what I've been seeing out of other Intel Sandy/Ivy Bridge systems too in terms of the delta between releases. The past four releases were all tested in their stock configuration with stock settings and using the open-source Radeon Linux graphics driver.
The power consumption was automatically recorded with the performance results in a fully automated manner in conjunction with the benchmarking using the Phoronix Test Suite open-source software. The power was monitored via a WattsUp AC power meter.