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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."
I may sound like a jerkwad here, but why waste all that battery power watching a dvd when you could watch the divx version off local storage?
Linux is a popular choice for netbooks, where battery life is paramount.
You mean "was", until Microsoft decided to keep Windows XP alive in the North American market for a few more years at bargain-basement prices per copy.
Is the kernel compiled to be tickless? http://kerneltrap.org/node/6750
We need a -1 TrollFeeder option
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
And people expect an average computer user to want to use Linux when they have to make sure their kernel is compiled right to do basic power management?
Ding Ding Ding. We have a winner folks. This is the answer. You need to have a tickless kernel otherwise the tick timer keeps the CPU from ever making it to those deep C states for any decent amount of time. In effect, the kernel keeps asking everything,"got anything for me". The CPU equivalent of "are we there yet" or "can you hear me know".
Who are you? The new #2 Who is #1? You are #617565. I am not a number, I am a free man! Muhahaha.
This is just the same problem Noted in XKCD.
Good battery life is not cool. Open source software, especially a mutt like linux, is all about cool.
Good battery life requires annoyingly huge amounts of microoptimizations and chipset-dependent tricks. Which is most definatly NOT cool.
Incorrect, at least in this case.
This problem has nothing to do with whether it is cool or not to squeeze and extra hour or two out of your notebook... This problem has to do with hardware support.
Linux developers continue to have trouble getting access to the hardware they need. Hardware developers are frequently unwilling to divulge the necessary secrets for F/OSS developers to write good drivers... And those same hardware developers are frequently unwilling to devote the time/money/effort necessary to write good drivers themselves...
So you wind up with half-crippled hardware under Linux. You get video cards, motherboards, hard drives, motherboards, etc. that won't properly spin down or hibernate or sleep or whatever.
Other folks in this thread have mentioned that this particular notebook ships with an ATI video card. ATI has notoriously crappy Linux support. This is a video card we're talking about... Geeks love video cards. It doesn't get much cooler than 3D graphics - look at all the time and effort going into projects like Compiz.
I can almost guarantee that if ATI would open up their documentation you'd see better battery life just as quickly as folks could code it.
"Work is the curse of the drinking classes." -Oscar Wilde
And people expect an average computer user to want to use Linux when they have to make sure their kernel is compiled right to do basic power management?
No, you expect the average computer user to install the mobile or laptop version on a laptop, which come premade specifically with optimizations like these.
One size does NOT fit all.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
But why should the average user have to worry about tickless
after all other OSs figure out your hardware and install the right options. A distribution could worry about the user experience and take care of this automatically or, at worst, ask you if you are installing on a battery powered system.
There is utility in having one entity responsible for the ease of installation and not punting it to the varying knowledge/skill levels of the user.
If Microsoft and Apple can do it....
Would you? Really? Cause I have been using Linux exclusively for my servers, desktops and notebooks for years and I didn't know there was a "laptop" ubuntu. Or suse. Or redhat.
Actually, I still don't know that. But I will take your word for it that something like that exists in some niche under a rock. Everything does. Linux distros are like porn on the net, if you can think of it, someone has done it. And heck, there are probably even supported ones from the three distros above maybe. Just I never heard of them because I haven't cared enough to look.
Which brings us to the odds of "the average computer user" having heard of them: Zero. Zip. None, Nil.
Plus, they have absolutely no conditioning for it, coming from either Mac or Win, where you don't need a magic special install to make your laptop work with your OS. You just do it.
So basically this isn't negating the OP's point, but instead reinforcing it. It is just another reason for people who aren't geeks to say: linux, I tried that but my battery life cut in half, so I put Win back on my machine.
7. What we cannot speak about we must pass over in silence.
I think many of the posters here, who all have great ideas and suggestions, are missing the point of the OP.
Why is an out-of-the-box XP machine performing better than an out-of-the-box Linux machine?
The Linux community shouldn't be saying "try this" or "tweak that" or "install this device driver" or "switch your hardware"... they should be working on building those into the next revs of the OS and making them part of the default configuration (or at least an easy prompt like XP offers).
-David
My biggest objection to using Linux (and a major reason why I tell less technical friends/family to avoid Linux) is because of posts exactly like this.
My first Linux install was Slackware (if I remember correctly)...back in 1998. That's 10 years. And for all 10 of those years, my experience with Linux has been like this...
Linux Community: 'This new version of Linux is totally great. Easy to use, great hardware support, best Linux ever. Totally better than Windows!'
Me: "Ummm, that's cool and all - but I have a problem with X"
Linux Community: "*I* don't have a problem with X! I don't even believe you have a problem. Where is your proof? It's totally not a problem with Linux, if it's even a real problem at all."
Me: "Umm...okay. Well...all I want to do is be able to X (where X was get on the internet, hear sound, use a wireless network card, have decent battery life - all of which were or are problems). Here's more information....
Linux Community: "You are using Y? Y is worthless. Everyone knows Y isn't supported in Linux because of XYZ. You either need to write your own driver or get a real Y."
Me: "Can you tell me, specifically, what Y I should buy?"
Linux Community: "*I* have ABC and it works great. But it's more than just what is on the box, it's the chipset and stuff. It's kind of hit or miss.'
Me: 'Wtf? This sucks....I'm going to run Windows'
Linux Community: 'N0ob.'
*six months later*
Linux Community: "Great news! We've totally made it so you can do X"
Me: 'Wait, last time you told me you could do X, and that it was easy, and free, and better than Windows. When I said I had problem doing X, you all told me I was crazy and to RTFM!'
Linux Community: 'Oh well....yeah...in the past, we've had some problems with X. Some users couldn't do X at all, but now we've totally fixed it! Now Linux is is totally great. Easy to use, great hardware support, best Linux ever. Totally better than Windows!''
--------
You get the idea. Months after getting flamed for complaining about how my wireless network adapter doesn't work in Linux, the Linux community raves about how they've improved wireless support.
I've had plenty of problems with Windows....but when I have a problem with Windows, at the very least, people *believe me*.