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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.
Truth is: Linux is not specifically intended to have laptops as end target, think how bad is the experience with suspend/hibernate in Linux, look how horribly bad the wireless is supported (ok, also Intel's fault, but ever tried get the wireless up and running after your basic installation of many distributions?!). Then what to say of early laptops 'burning' with Linux? And lack of support for proper FAN regulation that makes them tenfolds noisy (ok, because the vendors exchanged their fan specs just with M$ sometimes), and so forth.
In general the FOSS community seems to me more oriented to "as long as is works" and "as long as is as powerful as possible" philosophy (ok, sometimes Power Saving rules are quite much odd, too). Serously, Linux has done many steps forward, but we're not (yet) ready for the desktop, on a laptop. Your mileage may vary depending on the distribution.
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.
I had 6.5 to 7 hours when the battery was new, on Arch Linux with every useless thing off (Bluetooth/WLAN).
Didn't tweak much, but I think Ubuntu keeps everything on and anyhow, Ubuntu has alot of tasks running compared to Arch (like, 200 vs 20 if you ignore kernel threads.)
Don't be an a-hole. There was a time when you too were ignorant about powertop.
Yes, what kind of moron doesn't know about things that aren't installed?
If you were blocking sigs, you wouldn't have to read this.
XP's default file system is NTFS, and NTFS is journaled, so I don't think Linux gets an easy out there...
When it *is* the intended OS, it's usually a highly customized version/distribution that's optimized perfectly for the hardware, too. My Dell Mini 9, for example, gets about 5.5h of battery life with the Dell-branded Ubuntu installation. When I wiped it and installed another distro of my choice, the battery life dropped to 3h. While I loathe Ubuntu, I ended up going back to their Ubuntu installation because a netbook needs that kind of battery life.
If you believe everything you read, you'd better not read. - Japanese proverb
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.
Another advice:
Use laptop_mode (http://samwel.tk/laptop_mode/)! It gives me additional hour on my 4 hour battery.
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)?
Powertop is a good tool and a dead easy install to add. I also have a custom Linux remaster that I did that runs openbox and based on the latest ubuntu 9.04 and its focus is on power savings and running on older hardware. It has a utility with a gui that lets you tweak various options and users have reported better battery life. It is called wattOS and is listed on distrowatch. Check it out at http://www.planetwatt.com/ tks.....Ron
The only Linux distro that give me more battery life then Windows is Opensuse 11.1
Have you tried that one already?
Really? I wondered why since most laptops have myriad settings in their BIOS for power management that they say to turn off BIOS power management when using software power management. I always wondered what exactly was the advantage of using software power management at all. I mean why not turn off software power management and use the BIOS settings exclusively? Are these 'microoptimizations' the reason?
...
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.
The device I work on has received industry recognition on its battery life and it runs Linux. But it's an ARM based handheld consumer electronics device. (I won't name names)
The tremendous amount of work our developers put into cutting every milliamp out of the system in the idle states is how we got the device so low. Out of the box on a random platform the energy saving features of Linux are non-existent. Add to this that on x86 systems there is a mess of different power savings interfaces and standards, some of them pretty badly implemented others just badly defined. You can tweak Linux in about two days to be power efficient on a particular laptop with a little know-how and a compiler. But your effort will be wasted on 90% of the other laptops out there. I blame this on Linus Torvalds for not recruiting a power expert to bring in and merge all the different patches necessary for good power savings on Linux. And on the immaturity of Linux's power infrastructure (doesn't exist). Providing only a primitive way for drivers, kernel subsystems, and userspace to communicate power needs.
I have a Thinkpad W500 with the 2.8Ghz Dual Core and the 9 cell battery. I'm able to get more than 5 hours of battery life with linux. Watching a movie I'm still able to get more than 3 hours without any issues. If you would have gone to thinkwiki.org you would have found out that the W500 comes with switchable graphics. It comes with both a discreet ATI graphics card with 512MB and an integrated Intel GMA 4500HD. Probably you main culprit is the dual graphics. If you leave switchable graphics on and run the Intel driver, it will still have the ATI graphics chip running at full speed. If you just enable the ATI graphics and run anything but the FGLRX drivers, it will run the chip at full speed thus killing your battery life. Intel's GMA 4500HD is the best supported right now and it's what I run under Linux. Once you work out the the graphics issues, you should be in much better shape. The Intel GMA 4500HD is also under heavy development and you need to run the latest kernel. I roll my own from kernel.org.
Once you get your graphics sorted out, use powertop from there.
Also, Vista and Windows 7 can use the full extent of the W500. To roll back to XP is a step backwards. Yes, it needs more memory, so give it more memory.
Also, why even post this on Slashdot? If you would have done your home work, and posted in some thinkpad forums, you would have gotten this solved.
To say that Linux's power management is awful compared to XP or Windows Vista is just naive. I have had XP, Vista, and Windows 7 running on this laptop. And Linux gives me the best battery life.
"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.
Not to mention the hassle of having to carry so many physical dvds around, a flash drive or hard disk is massively more convenient.
http://spamdecoy.net - free throwaway anonymous email - avoid spam!
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).
It's been my experience that the average user has never done an OS install. If they were to give it a go and compare an MS OS install to a Ubuntu install I think you'd find that in more cases than not, the Ubuntu install goes more smoothly for them. As an IT professional I'm never surprised when an MS OS install does require a little bit of magic or voodoo tom complete successfully. Linux seems to have gotten to the point (Ubuntu anyway) where the odds of running into some sort of install snag are the same if not less than an MS OS install. Jumping through technical hoops aside, it takes less than 20 minutes to install Ubuntu on a PC (including the apps I want). I don't think I've ever completed a Windows install in less than 1 hour (just the OS, no apps). I find that difference alone compelling.
Having recently installed Vista, 7, and Ubuntu on my laptop, I think Ubuntu was the most difficult. It asked things in unexpected ways and the timezone map was atrocious. I wouldn't say it was significantly more difficult but it was quite as easy as Vista or 7.
Yes, Linux not being as power efficient as other OSes doesn't have anything to do with Linus Torvalds thinking things like ACPI are "a complete design disaster in every way."
The ACPI specification is available to anyone.
GLaDOS for President 2016! "Well here we are again. It's always such a pleasure." -- GLaDOS, 2011
Um Linux is a tickless kernel now?
Last I heard, the "tickless" kernel was more of a "tick less" kernel in that you could give it a clock divider to tick less often. So you could have it tick 100 times a second or 10 times a second instead of 1000 times a second as it does by default.
Of course, I have only encountered this in the realm of running VMs. You can get some pretty impressive clock skew under ESX with an older stock kernel and no tuning (hours a day)
-Steve
"I opened my eyes, and everything went dark again"
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!
Yes, same here. This article surprised me; I'm running Kubuntu 9.04 on a Dell Latitude D630. It was old and abused before I got it, and I still get ~4 hrs battery life doing research and coding projects. Default install of Kubuntu, no tweaks, default power options that it came installed with. I've been very pleased with it, especially in regards to suspend/resume - I never shut this thing down completely. Always using a wireless connection as well. I can't say much about the disk drive power usage though, as I never use it.
ATI have released some of their documentation (most of the baseline info about the R600/R700 chips). So they do deserve some kudos for that; they have released far more register information than Nvidia for example. As far as I know they haven't released all the info needed for really good powersaving, so maybe a little encouragement is required rather than chastisement. A good way to encourage them is to buy their hardware :) Personally all the graphics chipsets I have bought recently have been ATI, precisely because they have released far more information about recent chipsets than any other mainstream graphics chipset manufacturers.
Yes, it's all the hardware makers' fault, they won't give kernel developers enough information to build fully functional drivers. It's not fair to compare it against Windows, since Microsoft relies on the hardware developers to build their own working drivers. But at the same time, Linus refuses to create a stable driver API/ABI. This is 2009, not 1999. If there was a stable, supported binary interface for 3rd party devices to use, vendors would use it, and you'd have a lot more fully functional device drivers.
Life's a compromise and if you aren't willing to compromise, you're going to miss out on things. Like battery life.
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.
the Netbook remix does not in any way include a recompile of everything. It is not a port, it is just a few extra programs.
It consists of:
* 1 full screen application launcher
* a program called "maximiser" that makes windows open full screen with no decoration by default.
* A theme for gnome-panel
* A "go-home" panel applet that brings the launcher to the front
* A Window switcher applet that replaces the taskbar, and also provides an equivalent to the title bar of the currently focussed window.
* A preference to switch back to a regular gnome desktop.
At the moment, the netbook remix is purely about appearance. It works very well on desktop machines as well (particularly ones with lower resolution screens), and on earlier netbooks like the EEE 701 (with an Intel Celeron, not Atom)
You can install it on any Ubuntu machine simply by installing apt-get ubuntu-netbook-remix.
I am currently running it on my desktop machine at home - an Athlon 64 X2, which is not only not an Atom, not Intel, but is even 64 bit.
Advanced users are users too!
My battery life is great and better than I would get under XP. The root of the problem is ACPI, an intentional free software sabotage (link contains email from Bill Gates, quotes from Linus Torvalds and Intel engineers). XP has very poor power management and gnu/linux can only be worse on the worst of hardware where ACPI is not working at all and APM is not an option. The efficiency of gnu/linux, when it works, should be obvious from the choices Google and IBM make. These things can be obvious on gnu/linux desktops though programs like KPowerSave, which should tell you how well ACPI is working for you. It works for me. If it does not work for you, you now know why.
The next generation of ARM netbooks and tablets will be running GNU/Linux and they are going to have 10 hour battery life, aka better than your iPhone. The sooner makers drop ACPI and other poisoned specs for free software, the sooner we will all enjoy consistent and reliable computing.
Friends don't help friends install M$ junk.
You're comparing apples to oranges. The out-of-the-box-XP machine is being compared to a linux-put-on-a-windows-box machine.
If the original poster wanted a linux computer that has great optimizations out of the box, then maybe the original poster should have bought a laptop from system76.com or linuxcertified.com or something.