For this article we've decided to not only deliver power benchmarks from Ubuntu 7.10 and Ubuntu 7.04 to compare the tickless kernel effect, but we have went back and retested all of the Ubuntu releases going back to Ubuntu 5.04, or also known as Hoary Hedgehog. With the past six Ubuntu releases we had tested the power consumption of a Lenovo laptop when running from its AC charger and off the battery, when the system was idling and then again under load. We had also monitored the temperature of the Intel Centrino mobile processor. You may be surprised by the results of Ubuntu's power usage.
thank you again for this really great article! it is exciting to read articles about this topic.
well, it is very sadly that they are not able to reduce ubuntu's power consumption.
perhaps they're going to get it with upstart. i recently read a great article about its future and it seems very exciting (http://liquidat.wordpress.com/2007/0...starts-future/)
in short: less services/deamons -> less power consumption (why do you need a cupsd when you don't have a printer?)
but i would like to see a test with the current fedora 8. they have optimised the whole system for less power consumption. i would say that it had less power consumption than ubuntu/other distris...
I noticed you mentioned that you used PowerTOP to measure the power usage. PowerTOP can also display the processes with the most CPU wake-ups, which gives us a good idea which processes are consuming more power.
Of course, this requires you to compile your own kernel.
i'd be curious to see the power usage difference between a win OS (say, XP or Vista) vs Ubuntu- even if we could see just 1 or 2 benchmarks vs ubuntu, it'd show that open source actually does have better programmers than some of the big guys, like M$
(please excuse the dreadfulness of this post, it's midnight and i'm tired)
I am curious about your powertop results. What processes are causing interrupts? On my laptop, the radeon driver is generating a 60Hz interrupt. There are also other problems, but the radeon driver is the worst offender.
To me, the most interesting benchmark for a laptop is how long the battery lasts while playing a DVD.
From what I understand, the bset thing to reduce power consumption is to get rid of all the periodic interrupts so that the processor can go to sleep when the machine is idle.
The firts thing i'd turn off is tracker as it keeps my hdd scanning all the time. If you ask me it should never have been included at this stage until it could be made less demanding.. Its very IO intensive and also eats the cpu a bit so i'd guess theres quite some power going there.. unfortunatly i don't have a meter to test for my self..