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Why Is Linux Notebook Battery Life Still Poor?
Ganty writes "I recently purchased a Lenovo W500 notebook, and after 'downgrading' to XP and creating a dual partition, I found that I had a battery life of nearly three hours using the long-life battery, at this point I was a happy camper because it means that I can watch a DVD during a flight. I then tried various Linux distributions and found the battery life under FOS to be very disappointing, with an average of 45 minutes before a warning message. After settling on Ubuntu I then spent three days trying various hardware tweaks but I only managed to increase the battery life to one and a half hours. Unwanted services have been disabled, laptop mode has been enabled, the dual core CPU reduces speed when idle and the hard drive spins down when not needed. Obviously Apple with their X86 hardware and BSD based OS have got it right because the MacBooks last for hours, and a stock install of MS Windows XP gives me three hours of life. Why is battery life on notebooks so poor when using Linux? Some have suggested disabling various hardware items such as bluetooth and running the screen at half brightness but XP doesn't require me to do this and still gives a reasonable battery life."
On my Samsung NC10, Windows gives me about 6.5 to 7 hours of battery life, Ubuntu about 4.5 to 5.
I get 10 hours on winxp on my eeepc, and 7.5-ish on eeebuntu.
I'd love to know what to do to optimize eeebuntu more, since that's what I need for work.
True. But if the original poster had supplied a bunch of config and log files, I'll bet there would be a bunch of people here providing more relevant technical solutions. Unfortunately, performance questions that seem very general often have very case-specific answers.
XP's default file system is NTFS, and NTFS is journaled, so I don't think Linux gets an easy out there...
Agreed. Simple web browser usage used to compare Linux and XP shows a 25% _increase_ in battery life under Linux. This was mostly doing research and reading emails. Flash sites tend to draw down the battery so I hold off on those until back on AC power. this was with a work issued laptop from Dell. I don't recall the model.
Yep, I never spell check.
More incorrect spellings can be found he
I've personally experienced issues with my laptop BIOS. It works properly in Windows, but a lot of the ACPI functions just flat out don't work in Linux. This is due to a compiler that lets the code compile with errors (Mainly functions that don't return a value when they should). This allows the BIOS programmers to be lazy, and write half assed power functions that don't work properly.
You can fix a lot of these issues by following the instructions in one of the links below to decompile that portion of the BIOS, and recompile it using the Intel compiler. It isn't easy, and certainly isn't something an user should ever have to do. It did fix a lot of the power issues with my HP laptop though (Running hot, not booting on battery power unless a key was pressed, hibernation).
See
http://www.osnews.com/thread?230516
http://ubuntuforums.org/showthread.php?t=1036051
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/272247?comments=all
In this instance, you can blame MS's poor compiler for Linux's poor battery life.
As one of those non-techies who enjoys reading /. for the brilliant article summaries, insightful commentary and the sterling sense of humor of many posters, this little tale explains exactly why I am not willing to switch away from a mainstream operating system. I think I'm reasonably tech savy for someone who's never taken a computer programming class, but wow -- none of this makes the slightest degree of sense to someone like me. Can anyone explain why my initial gut sense is an over-reaction? Should my replacement computer (another laptop) be Linux (other than Apple)?
Just my own experience, but I've never seen differences in battery life that are this extreme. Linux has always been worse, but never more than about 10% on the laptops I've used, with one exception.
The only time I've seen a huge difference is on an HP laptop that I currently use as an SVN/Trac/CUPS server. The machine has a BIOS bug that prevents me from using ACPI in Linux, and HP never released a patch to fix it. The only way to keep the machine stable in Linux is to boot "acpi=off, noapic, nolapic". With no real power management, it drains mighty fast, even with all the hardware that gets disabled booting this way (webcam, wireless, etc).
On the other hand, a few years ago I owned a wonderful Sager laptop. With two double capacity batteries and a regular capacity battery, I could get a full 20 hours of battery life from the three (8 hours for double, 4 for regular) running Linux (Gentoo at the time), which was within 1 hour of the average total when I ran XP.
Linux does have worse battery life, for a number of reasons, but the difference doesn't seem significant on most hardware. It all seems to depend on hardware quirks in your machine.
"Linux is dead, long live Windows 7!"
er, don't know about dead, and I wouldn't say "long live windows 7", but I will admit the battery power options are very impressive on Windows 7. Not only can you change the obvious like cpu speed, but you can go all the way down and adjust how long the CPU fan should be on if you're on battery, and it can change according to which battery profile you choose. It has more options than I've ever seen on any program, even more than NHC.
my karma will be here long after I'm gone
My experiences are different. On all the laptops I've owned, and all of my friends laptops Ubuntu has a better battery life than XP. Something about anecdotes? It probably comes down to the which OS is better with which hardware.
There are 11 types of people, those who know unary and those who don't.
Well, perhaps it's the distro? Or the hardware. On my Dell Vostro 1000 with a 6 cell battery, I get at absolute maximum 4 hours of battery live on WinXP. On a slightly stipped-down Mandriva Linux I've managed to squeeze 6 hours of use out of it while watching movies. Of course, you could say this isn't an _entirely_ fair test as I was running both the system and the movie from a USB flash drive, but considering I did nothing special in the installer, just told it to install to the flash drive, I'd say it's fair - if you could install Windows to flash that easily I'd run it from one too. Plus with my full version of Mandriva 2009.1 using KDE4 I still get at least as much battery life as I get on XP - and it actually last longer than XP does for gaming (specifically World of Warcraft).
The last time I installed XP on my laptop I had lost some, but not all, of the OEM-supplied driver disks, and it ended up taking me a total of about eighteen hours of solid graft to get it to work. Incidentally, I grew up on Windows, and have only really gotten into FOSS stuff in the last three or four years, and the last time I installed Ubuntu (which took about twenty minutes) it had already configured my screen to the right resolution, got the wi-fi and bluetooth working, got the frickin' bog standard ethernet adapter working, and suggested that I might want to download the right drivers for my GPU by clicking OK and typing my password.
When people say these things, I always have to wonder whether they have ever actually installed Windows. Maybe it's just me, but it takes longer for XP or Vista to simply copy the base installation to the hard drives than it does for me to set up Ubuntu, and I still have to look up which packages I need to install to listen to MP3s or watch DVDs.
Be smart, help people!
The last time I installed XP on my laptop I had lost some, but not all, of the OEM-supplied driver disks, and it ended up taking me a total of about eighteen hours of solid graft to get it to work. Incidentally, I grew up on Windows, and have only really gotten into FOSS stuff in the last three or four years, and the last time I installed Ubuntu (which took about twenty minutes) it had already configured my screen to the right resolution, got the wi-fi and bluetooth working, got the frickin' bog standard ethernet adapter working, and suggested that I might want to download the right drivers for my GPU by clicking OK and typing my password.
This is dead on! I tried to put XP on a laptop I found at the dumpster. Even after tracking down the drivers from the vendors website the bloody thing still didn't work right.
Pop in a Linux Mint disk and just like that I have a functional system. Sure, it has a few quirks (which I can't tell if it is the hardware or the software) but it's totally usable.
...and I still have to look up which packages I need to install to listen to MP3s or watch DVDs.
Try Linux Mint http://www.linuxmint.com/ it's an Ubuntu variant that comes with a bunch of the proprietary stuff vanilla Ubuntu doesn't come with out of the box. It's pretty slick.
Celebrity worship is a poor substitute for Deity worship and costs more to boot.