The Tests Showing Ubuntu 11.04 On A Power Consumption Binge
Again, the first result shows light desktop usage with Firefox, OpenOffice.org/LibreOffice, Nautilus, and menu navigation. While the lines are a bit cluttered due to seven lines close to one another and the auto-coloring being close, the average/peak/low values at the top are clear and laid out from the oldest Ubuntu release to newest Ubuntu release (left-to-right). Note: the latest Phoronix Test Suite Git code now has an improved color allocation scheme that should hopefully result in further distinctions between colors on future graphs.
These results show that for the ThinkPad R52 with an Intel Pentium M processor the first signs of Ubuntu 11.04 going through more power. In fact, the average power consumption is quite frightening. Ubuntu 11.04 LTS is burning through more power on this old ThinkPad than any other release tested, even going back to 2008 with Ubuntu Hardy. On average during this light desktop power consumption test, Ubuntu 11.04 was eating up 21.3 Watts where as Ubuntu 9.04 did the best at 18.9 Watts, which would have been at the prime of the R52's support life-cycle, and even the 2008 releases were coming in at 19 Watts. In 2010 these averages went up to 21~22 Watts, but into Ubuntu Natty we are now at over 23 Watts. The peak during this load was at 27 Watts, which is also a high (negative) point.
When monitoring the battery power consumption rate when pegging the CPU with running OpenSSL, the Ubuntu 11.04 power consumption in this case was not the worst of all releases, but it was not the best. When looking at the power consumption with the CPU being 100% busy, Ubuntu 11.04 Beta 2 did better than Ubuntu 10.10 but it is noticeably worse than the Ubuntu 9.04 and 9.10 where the ThinkPad R52 did the best.
The next test was when stressing the disk and CPU by running the PostMark mail server benchmark on the mobile Pentium-powered IBM computer. Ubuntu 11.04 Beta 2 with this load did slightly better than in Ubuntu 10.10, but it's still well behind where it was in the older releases. Ubuntu is becoming less power efficient.
At least the PostMark program itself is becoming faster with newer releases after the switch from the EXT3 to EXT4 file-systems.
No graphics tests are delivered for the ThinkPad R52 because Ubuntu 11.04 with its stock Mesa 7.10 package with the Gallium3D R300 driver was too unstable and frequently would lock-up when running OpenGL games on the Mobility Radeon X300. This is another place where the latest Linux code has regressed, but I will save that for another article.