The bug introduced during the development of the Linux 2.6.38 kernel causing excessive power consumption is very real, is occurring on many different hardware platforms, and has just been deemed a bug of high importance by the Ubuntu Kernel Team. This serious regression was just made widely known on Friday in my Mobile Users Beware: Linux Has Major Power Regression article and then further detailed in The Tests Showing Ubuntu 11.04 On A Power Consumption Binge.
At first, some were trying to write this off as not being a bug or just a Phoronix story, but it's proved to be a very real issue. Worst of all, it's living in the upstream Linux kernel and impacting all Linux distributions using 2.6.38+, which is already released as stable and it's still living in the Linux 2.6.39 kernel. The bug has been in the mainline kernel since the second week of January, that's almost four months!
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