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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."
Is your screensaver running SETI?
Probably not a good idea if you want to conserve battery life.
Linux is a popular choice for netbooks, where battery life is paramount. Does windows still have an advantage there?
Give me Classic Slashdot or give me death!
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?
I don't know how you can expect us to fix your problems when you won't even take the time to read the documentation provided with the release.
In order to solve your problem, you need to set the RANDOMLY_DISCHARGE_BATTERY flag in the kernel source to "0" at compile time. Ubuntu, as well as other "desktop" distributions, set this flag to "1" by default for some reason, but simply installing the source packages and recompiling your kernel will fix the issue.
Honestly, a simple well-tailored Google search and a few measly days of sifting through the docs would have given you this answer without having to waste everyone else's time.
The summary writer describes trying various Linux distributions and concludes that results under FOSS are poor. But FOSS comprises more than just Linux.
I was able to get my X41 tablet to have good battery life (a bit better than windows actually), but it took some doing. Powertop is a godsend, it pointed me to the i915 intel drivers as the culprit. Disabling DRI made a huge difference.
If you're running on an Intel platform, try running powertop. I can easily gain over an hour of battery life by disabling the services it recommends and reducing the screen brightness.
Here's some concrete evidence. Take a look at http://event.asus.com/eeepc/comparison/eeepc_comparison.htm in which Asus compares their different eee netbooks. Go to the battery life column and observe how, unfortunately, XP consistently outperforms Linux :(
And I have plenty of anecdotal evidence that power management works really well with whatever OS the computer was intended to run, and is alright-to-crappy with any other OS.
My MacBook Pro runs decently in OSX, and drains quickly in WinXP.
My HP Compaq laptop runs really long in Vista, though its still alright in Linux. (haven't done a comparison, though... But Linux still whines when battery #1 is almost dead, even if I have battery #2 available, installed, and at 100%)
The crux of the problem is that Linux is *rarely* the "intended OS" for any of these platforms, so the hardware manufacturer never invests any effort to make sure Linux power management drivers work correctly on them.
He only wasted you time and informed me and about everyone else who didn't know this. Thanks eln!!
Have you tried PowerTop? Discussed here. I haven't tried it myself, since my linux laptop is an ancient PPC. I have noticed a somewhat short battery life on my linux laptop though. Not sure why.
Gentlemen! You can't fight in here, this is the war room!
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.
This really is an issue, and hardware support varies. Your notebook seems to include an ATI graphics card. That's probably your problem. Last I looked neither the open source, nor the ATI graphics drivers supported power savings on the ATI cards. I have an Asus F8Sv, which actually gets longer battery life in Linux, about 10 minutes, even though when running Linux, I have an external hard drive connected. It's got an Nvidia Geforce 8600 graphics card, with Nvidia's drivers. (Mind you, this is with OpenGL composting enabled, under Kubuntu (both 9.04 and 9.10) The other big one is Intel cards, which are supported for most of their power management features under the driver Intel helped write.
maybe you should figure out what your settings are for linux?
The original poster tried that: "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."
I dragged my old 15" Powerbook (1Ghz G4) out of retirement to have a look at Ubuntu, and while this may be a totally unfair comparison since the PPC build is hardly going to be the major focus of their optimising, but the PB did run much hotter under Ubuntu than it did under 10.4, and fan control was much less precise. It's not surprising, since Apple made the thing and obviously designed OS X around all the various controllers and sensors in it and Ubuntu has to run on anything you can throw it at, but that would be what I put this down to.
I was not sufficiently experienced at the time to do much to cure it, but I did install some software that had been written to make the fan control better which did help a little to keep it cool, but I'm not sure it would last long away from the power adapter.
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.
Test your net with Netalyzr
You can run $sudo powertop and follow the suggestions there. Have you tried that ?
I use a Compaq F756NR, and get about an hour and a half in Vista, and maybe an hour fifteen in Win7. In Arch, I get a minimum of two hours. A fresh install only gets about 45 minutes - there is a power management package you have to install, and configure for how you want it to work. I've got mine set up to automatically scale up if the CPU reaches 80% load, and down once it drops below 50%.
I don't have my laptop with me, or I'd get you the package name. It's been over a year since I installed it, so I've forgotten :(
Learn about Photography Basics.
Perhaps the linux developers need to write more efficient code?
With recent laptops, I haven't noticed or cared, but I had a netbook before it was called a netbook -- the Sharp Actius MM10. And while I never tried it on Windows, it had one battery that supposedly lasts two and a half hours hours (that I remember lasting 3 hours), and another that supposedly lasts seven and a half hours (that I remember lasting 8-12 hours).
It's worth mentioning that I don't remember half the tweaks I did to this machine. With only a 15 gig hard drive and 256 megs of RAM, I installed Gentoo and used CFLAGS=-Os, custom-compiled my kernel complete with suspend patches and Reiser4 (practically a laptop mode all by itself), and otherwise modded it in every way known to man. I mean, I had a Fluxbox desktop with no menu, only the equivalent of alt+f2; because I didn't have any advanced power management running, I wrote my own Perl scripts to check the battery state, and to respond to ACPI events (lid closing locked it but didn't suspend, power button at various times would hibernate, or display a giant message saying "PLEASE DON'T PUSH THE POWER BUTTON, KTHNX"...
Also worth mentioning that Reiser4 wasn't the only prerelease software I used -- and it was prerelease, at the time. I backed it up frequently.
Still, I'm fairly surprised to learn that Linux battery life sucks on modern notebooks. My current machine was not built for battery life, so I've never actively run a test.
I suppose what's worse than that, though, is how much battery life sucks on modern notebooks, period, including netbooks. I admit the Transmeta chip felt sluggish, but on the other hand, can you buy any laptop today that'll run for nine hours on a charge, to where you can simply leave the power adapter plugged in at home for the day?
Don't thank God, thank a doctor!
I don't use ubuntu, but for me, my Arch setup with awesomewm lasts almost 1.5 times as long as windows. YMMV.
I think it's more likely that compiz which comes with ubuntu is the culprit here.
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.
And I get 7-8 hours on ubuntu with my netbook. ... but I get 10 hours in WinXP, and that's the point. We need a comparison.
I would like to know which version of Ubuntu he has chosen and what other distros he's done. Off the top of my head for distros I'd try:
1) Ubuntu Netbook Remix (Both Gnome and KDE)
2) Moblin
3) Puppy
4) Macpup Opera
5) Xubuntu
6) gOS
7) Damn Small Linux
Yep - either those who target netbooks or those which try to be resource friendly. If one can run on a much older system well then a newer system it should hum, plus not be such a big hit on the battery life.
I call it 'The Aristocrats'
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
Are you sure? My netbook dims the screen when I pull the power cord on both XP and Win7... though it might be the BIOS doing that.
Anyway my suggestion is checking if ACPI works as it should. AFAIK laptops are notorious for buggy ACPI implementations that are only tested with Windows. Linux now pretends to be Windows XP when doing ACPI stuff, before that they noped out some part of the BIOS to make it work with Linux but that wasn't reliable. Look into if you can change how Linux does ACPI and try that.
Perhaps you haven't configured your kernel or power settings fully even on my old Thinkpad 760 (Pentium 166) I got 50% more battery life out of Linux then Windows...
If you check your CPU freq via /proc/cpuinfo does it drop? Perhaps you are using the "performance" instead of the "Ondemand" CPU Freq governor...
Life is but a Beta test...
So it seems the posts here are telling this person to use a different method to watch the movie.
the question remains, why is Linux sucking up batteries at 2,3 times the rate of OS X and even Windows XP ?
...running a fairly powerful laptop, a Dell Latitude D630 (Core2 Duo T7500 2.2GHz, 4GB RAM, Seagate Momentus 7200rpm 120GB HD, nVidia Quadro NVS135M w/256MB RAM) on Fedora 10. I regularly run it for 4-5 hours on battery.
Comparing a MacBook to a PC is not really fair. Hardware specifically designed for the OS... or an OS designed specifically for the hardware... that's not a fair comparison to Windows or Linux and generic PC hardware. As far as I know, Windows does not tailor it's code to all Dell, Lenovo, Gateway, HP, and Asus laptops. Apple tailors OSX to Mac hardware. Perhaps the hardware manufacturers do, but it should be able to go both ways.
The HP Vista-Linux comparison is better.
I have not yet seen your "plenty of anecdotal evidence," I guess. :)
I think a better explanation is this: Linux's developers are not particularly interested in long battery life.
http://hardware.slashdot.org/comments.pl?sid=1347015&cid=29187931
I'd say though, that this level of customisation of linux in order to get decent battery life in comparison with xp is a barrier to takeup. the Linux kernel dev team, and various package maintainers need to switch on to this.
The hackintosh community has noted that netbooks run hot with Firefox (all versions),
but stay cool when running Safari. This problem is discussed here:
http://mydellmini.com/forum/general-mac-os-x-discussion/6550-my-os-x-mini-gets-pretty-warm.html ... but is not limited to mini9 hackintoshes. Other netbooks with heat issues run
hotter with firefox.
Perhaps firefox has a busy loop for event dispatching somewhere? I did a simple
test running down my battery, and firefox cuts it in half. (!) But that's just one data point.
Anyone know for sure?
kernel developers are smarter than that, and know that would be impossible to support. The real flag is PSEUDO_RANDOMLY_DISCHARGE_BATTERY.
"National Security is the chief cause of national insecurity." - Celine's First Law
I am using a W500 on Debian right now. Because this laptop has two graphic cards and because the ATI has no open source drivers, I use the intel card on Linux. I read a lot of reports about the ATI card using a *LOT* of power. Try disabling the Switchable Graphics in the BIOS.
We need a -1 TrollFeeder option
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
While I can't say that my Dell laptop's power management has been piss-poor under Windows (I can't really say that I used Windows on THIS particular computer that much, but I did on previous Dell models) and the power management was pretty excellent especially when the Intel speedstep software was running. If it helps, I run Fedora and Fedora and Dell laptops have been getting along fabulously for at least the past 6 or 7 version releases.
But one thing about running Windows that has always been a complaint and that's it's estimation for "time remaining." Whether looking at file transfers or remaining battery life, Microsoft ALWAYS seems to over-estimate "time remaining" or has at least reported the most optimistic figure possible. What I'm getting at is that it is QUITE possible that the Windows battery life you are reading is either untrue or unrealistically optimistic.
I know on my Dell Mini 9 running XP and watching video on battery power initially claims I have like 3 or 4 hours battery remaining, but before the two hour movie is complete, it wants to die.
The biggest source of battery drain on my netbook is CPU processing. No doubt with my other notebook, it would be hard drive usage followed closely by processor/gpu usage. This leads me to the next suggestion when using Linux -- use the graphics driver provided by nvidia or ati. They manage power better because they have the "secrets" that the GPL drivers don't have access to. Remember that a GPU is still a processor and eats power when processing.
Power management on laptops is all about paying attention to everything that draws power and being aware of it. For example, if it generates heat, it's using power... usually lots of it and cooling systems draw even more power as a consequence. Dial that speedstep down WAY low when unplugged.
it is perfectly fair to compare macbooks to a laptop machine, if the os being tested is the one that shipped with the laptop. They ship the device as is, their os choice is not relevant to how you should rate them for battery life
It's pretty funny that you assume he's a right-winger when his signature could just as easily support the idea of a public health care plan. Perhaps you should check your outrage at the door next time and try using your brain instead?
Hearing a Brit talk about the losing side of history is pretty amusing too. How's that surveillance society nanny state working out for you? Don't worry about all those rights you keep losing, you didn't need them anyway. Your friends in the Home Office will take good care of you :)
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
This is, of course a vast simplification, but it gets the point across. The linked to article also shows how to use laptop mode to address these issues and extend batterly life (although, it seems to me that there is a trade off in the ability of journaled file systems to perform correctly).
willing to spend a few grand a year for this goal
We all already spend a few grand a year for each student for this goal. We are forced to, on pain of going to jail if we don't.
The DC public school district, for example, spends close to $12,000/year per student, and has some of the highest rates of illiteracy, drop outs, and useless students by the time they are socially pushed through the system. When the same parents in that area are given the option of charter or private schools, they stand in line for three days in hopes of getting such a slot for their kids. The public system is - just like all government options - plagued by politics, inefficiency, unaccountability, and the iron fist of lefty labor unions that protect the worst of the worst who work in the system. Yes, please make sure that health care is handled the same way. That would be great.
Don't disappoint your bird dog. Go to the range.
It is no use setting sleep mode on the HDD if you leave Syslog running.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Oh, hey, I know you. You're the tech support guy from A&TT I spoke with last week. When I asked why my cell phone didn't turn on anymore, you asked me to turn it on and go to the configure screen. When I responded that It wouldn't turn on. You asked me why.
I've had to recalibrate my battery twice in Linux, with limited usefulness, and I suspect you're suffering from the same problem. Specifically, after the indicator shows a completely drained battery, providing I disable auto-shutdown the computer will continue to operate for a significant amount of time. - Run the battery completely dead. - Charge the battery with the computer turned off. - Run the battery completely dead.
XP's default file system is NTFS, and NTFS is journaled, so I don't think Linux gets an easy out there...
Do you leave your battery plugged into the notebook when you have the notebook plugged into the wall?
enjoy dramatically shortened battery life because of the heat killing your battery.
As others have said - check your hardware and hardware drivers, it's quite doubtful that it's your OS causing the issue.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
That wouldn't fit with the massive loss seen by TFS. Anecdotal, yes, but my old notebook ran ~3 hours on Windows or FreeBSD (sorry, don't know about Linux), using defaults for windows, and BSD compiled without extra drivers. I would expect FreeBSD to have a similar loss to Linux in that case (journaled file system). Also, the shared partition that both Windows and FreeBSD accessed was EXT3.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
The information you provide is ... well ... sparse. By far not enough to draw the conclusion you draw.
What about your wifi, bluetooth, are they on? At what power level? Is the webcam always on? Is the optical drive doing things it shouldn't?
Nevertheless it should indeed be said that out of the box, Linux battery life sux.
0x or or snor perron?!
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
The W500 actually comes with 2 video cards, one discrete and another integrated. It's been found that if you switch from the discrete to the integrated, your battery life jumps up from the ~2.5 hours of battery life to over 5. I'll dig up the link here.
I'm surprised, my experience with Ubuntu 9.04 is very good on similar Thinkpad hardware. After upgrading from a decrepit IBM T42p to a Lenovo T61p (UXGA->WUXGA = similar screen size/power demands to the hi-res W500), I still get ~4:00 out of the Thinkpad extended battery.
Some ideas; perhaps these will be useful: .45A Seagate, and my experience was dramatic: 30-45min more battery time from that change alone. When I upgraded the recent hdd, I made sure to select one with less than .5A consumption.
- There is a bios setting on the Lenovo-era Thinkpads where you can force the screen to high brightness. My Ubuntu install manages this correctly (i.e. turns it on when on line power, off when on battery). However if yours does not kick the brightness to the normal range off line power, it'll kill the battery faster than any other factor. On high display brightness, you will be lucky to get more than 90min on battery.
- Hard drive power consumption does make a significant difference, and for that, Windows does tend to spin down the drive more frequently. With a high-load drive the difference can be pretty dramatic, but a more efficient drive closes the performance gap even if Linux isn't as aggressive with drive power management. For example, with the last upgrade to the T42, I replaced the old 1.1A IBM drive with a
- Check your display drivers. On the T61 with the default Ubuntu installation, the CPU load increased with the open-source video driver, because it's compensating for certain unknowns in the GPU by offloading to the CPU/being more inefficient. Loading the Nvidia driver not only increased performance (a lot), but (again) noticeably reduced power consumption.
In short, optimize, optimize, optimize.... and sometimes that means installing the right driver, not stripping things down.
I think not...(*poof*)
Oddly... I have some anecdotal evidence from a laptop that came with Linux that backs up THAT statement. I use an N Series Dell Laptop that came with an Ubuntu installation and I've always had solid battery life. I did an upgrade of the Ubuntu distro and it continues to be true. So maybe Dell paid some attention this this? Who knows.
Oare we talking notebooks or netbooks? Linux on my netbook had a lot more battery life then XP or OSX on the same netbook. Win 7 may beat it or be close. haven't fully tested it yet. It could also be that the SSD drive is liked more by Linux then XP for me.
But have others have said, are the power saving setting turned on? I thought those were turned off by default. Is it even a fair test? Are both machines the same? Both OS set to turn the same things off?
What do you mean? I just turned on my laptop linux and it always lasts ove
Really? Wow. I must be doing something wrong as well. Can you detail your setup a bit?
funny, it looks pretty clearly an argument to have a public option, comparing it to things that most would approve of.
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
It's sadly true that almost all Linux applications / distributions have not taken writing-to-disk into account to reduce power. On the other hand, video / 2G / 3G graphics acceleration in hardware makes a huge difference, which is why I would really like to see more companies offering more in terms of stable hardware acceleration.
Why would the manufacturer lie in a way that makes its own product look worse?
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.
Because linux is fucking terrible for desktop use.
The battery life on my desktop is just fine.
Look in cron and disable stuff you do not use, especially locate.
Do not use the optical drive and make sure you are quiescing it.
Turn-off access time modifications for the hard disk.
Turn off fsck on boot.
Turn off periodic SMART status checking (on some drives this spins it up).
Tune the time to idle the drives and the periodic disk flusher (you have basically UPS with a laptop anyway).
Turn off swap.
Use a light simple window manager such as fvwm2 instead of something like gnome where lots of files are being accessed all of the time and you have many procs/threads running and the neat effects burn the battery.
Find the docs to your graphics drivers and tweak the tunables to use as little power as possible (this will give you much more than you likely expect).
Turn off bluetooth and wireless when you are not using it.
Don't use any of the crazy sound daemons.
You probably don't need wake-on-magic-packet for a laptop, turn it off, it helps a lot for some NICs.
Do you use multicast for wireless, most likely not, read the docs and figure-out how to get your driver to ignore that, it can conserve more power on some cards.
With some of the older chips USB was very power hungry in sleep (if that's your case tweak what you can so that it does as little as possible, likely turning off the wake on keyboard and mouse since you shutting and opening the lid should handle that).
Install a flash blocker and/or ad blocker and use gnash where you can instead of the adobe version.
Have you looked at your video drivers? Many laptops (sorry, haven't looked up your model) have video acceleration built into the video card that isn't always utilized by open source drivers, usually due to poor hardware documentation.
FWIW, switching to Nvidia blobs increased the battery life of my laptop quite a bit, especially for DVD / movie playback.
I went to eat some animal crackers and the box said, "Do not eat if seal is broken." I opened the box and sure enough..
My experience on my HP notebook is that Ubuntu 8.10, at least, kicks both Vista and XP's ass in battery life.
The world's burning. Moped Jesus spotted on I50. Details at 11.
The OP finds that battery life is poor using Ubuntu but then asserts battery life is poor in free operating systems in general. Spot the elementary mistake...err..that's the mistake of logic, not the choice of OS ha ha ha
Yes the kernel will be tickless by default but that's not really worth anything when multiple services are (in effect) polling continuosly....the wireless never sleeps, the bluetooth never sleeps, the metasearch crawler never sleeps, the CPU and disk are constantly busy...and battery life is woeful...surprise. Ubuntu with its Compiz UI would be better compared to Vista than XP because they are both (Ubuntu and Vista) intrinsically resource hungry. If good battery life is a priority then XP or a distro without all the UI candy and make for a much better choice. Plain old Debian with Gnome or KDE (or Xfce if composited desktop and nice transparency is required) will fare much better than Ubuntu every time, will have better performance all around and has the added benefit of negating the need to ever visit the truly dire Ubuntu Forums.
shocking that P & GP posted as AC
Wah Sig!
I loaded the movies into a RAM disk and set the hard drive to power down, shut off syslog, and removed the DVD drive completely. Try that on a Windows box!
You mean like using RAMDiskXP to do exactly the same thing?
Yeah, my Asus Aspire one lasts for about 3 hours on a charge under Linux.
Could you post the distro/tweaks you did to get that? Mine gets about 2 hours with Ubuntu Jaunty Netbook Remix...
No sig for the moment.
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
Stop feeding the trollfeeders, you trollfeederfeeder!
Making one of your products look better than another of your products doesn't really make any of your products look worse...
There are very few modern models where battery life is given as different from XP. In those cases the difference is rather small (not like what the article poster is experiencing). In at least one of those cases, the Linux hardware configuration is different than the XP hardware configuration. (Different flash drive size, there may be other changes such as a different WLAN card. For example, the Dells that have Ubuntu preinstalled have a different hardware configuration than non-Ubuntu Dells of the exact same model number.)
For example:
1101HA is given as being available with either XP or Linux. Only two battery life numbers are given, one for each possible battery configuration.
The 1002H is XP-only and seems to be one of the worst performers in the 10" class (5 hours)
In my experience, the most common causes of lower battery life under Linux:
NVidia chipsets. The power management in their driver is one of their lowest priorities. If you want games, you're going to have to sacrifice battery life.
Sometimes the "ondemand" cpu speed governor can be a little flaky and step to high speed way too quickly.
Keep in mind that's Asus's own Linux distro which most people regard as not being that hot. It may be missing some power tweaks available to other users. With the exception of Nvidia-graphics based laptops, I've usually been able to get much better real-world battery life on a machine with Linux than Windows. (Exception being that I haven't gotten FSB clock changing working on the Ubuntu partition of my Eee 1000HE yet - downclocking the FSB is the core component of Asus's "Super Hybrid Engine" power management scheme.)
retrorocket.o not found, launch anyway?
Go to your slash dot preferences; Select "Discussions"; Select "Viewing"; check "Disable Sigs". (of course you have to be a subscriber, but you can still post as AC if you like.)
Sigs are like bumperstickers. Once in a while they are amusing, but usually they are irrelevant and irritating.
As tepples said, it's pretty clear that the OP is trying power management. Also, to be fair, a lot of BIOSes have unsupported and undocumented quirks that break ACPI. These can be worked around by providing an ACPI or motherboard driver for Windows, but Linux has no such joy. Having power management working properly and extending battery life in Linux relies on having a BIOS that is ACPI compliant, among several other factors.
If you believe everything you read, you'd better not read. - Japanese proverb
I'd love to have power management. I could finally find out things like how much charge is left in the battery, and I could enable CPU throttling and so on.
Unfortunately, the only way to make Linux boot on my (2 month old) laptop without causing a kernel panic is to disable ACPI. The kernel doesn't understand the ACPI tables, whereas Vista does (apparently XP too). It's not clear whether the problem lies with Phoenix or the kernel people, but it doesn't work. Can't even power off at shutdown. :-(
Fortunately, the Nvidia driver doesn't use ACPI for its power management, so the GPU throttling works just fine. Everything else works too, even the built-in webcam and WLAN!
-- Steve
The only Linux distro that give me more battery life then Windows is Opensuse 11.1
Have you tried that one already?
Because linux is fucking terrible for desktop use.
The battery life on my desktop is just fine.
Really? Battery life on my desktop sucks. It dies as soon as I remove the power cord.
Hardware specifically designed for the OS...
As far as I know, Windows does not tailor it's code to all Dell, Lenovo, Gateway, HP, and Asus laptops.
Come on, you refute your own argument. Hardware manufacturers do design their laptops to play well with Windows, in general. It is only recently that they have even considered installing linux as a feature. Most of them are probably still way behind on making their hardware play well with Linux. The main complaint I always hear about Linux is about having to do fancy things to make drivers work. So all comparisons are valid.
Well, DUH, it HAS to be perfectly optimized for the hardware.
Battery management requires checking every single pin on your hardware and ensuring that you've set the i/o correctly for sleep mode.
If you have even one pin with a pull-up resistor set as an output, then you'll get lower battery life than the nominal case. If you have just random I/O on unused pins, then you're going to get greater drain than ideal.
I'll qualify that statement by saying I'm an Electrical Engineer with embedded experience. One of the products I worked on was a GPS / VHF tracker with a 12uA standby current. Another was a VHF tracker with an 8uA standby current. Slight modifications to the firmware would bring the standby current up to 50-100 mA. That's more than 1000x more standby current.
My experience dealing with Linux developers (and realistically, software developers in general) is that they're all terrible at determining the link between hardware and software. Look at the derision you get online towards C. Linux devs are worse -- if you're not running their exact hardware on a machine you bought in the last month, then it's your problem, not theirs. "Weird, it works here. Have you tried recompiling the drivers?"
It's fairly easy to map these pins, BTW. All you have to do is set everything to an output, set it to 0, and then turn everything to an input. Everything that's high has a pullup resistor. Do the same with 1 and everything that's low has a pull-down resistor. Now you know which pins must be inputs when you're not using them.
Of course, since you taught yourself programming with Ruby on Rails, you know all this, right? It's not like you'd have to have some low-level knowledge of the hardware in order to effectively make a complete synergistic hardware and software package.~
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
Buy an airline power adapter and quit whining. http://www.buy.com/prod/lind-automobile-airline-laptop-power-adapter-lind-automobile-airline/q/loc/101/10392022.html
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.
So maybe it's time for both kernel developers and distribution packagers to focus a little bit more on which hardware users are buying.
Which is not multi (4+) core servers, but rather cheap laptops and netbooks.
And, anyway, lower power consumption and better efficiency will probably also benefit the "big iron".
Maybe Computers will never be as intelligent as Humans.
For sure they won't ever become so stupid. [VR-1988]
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.
The author recounts his own personal experience with poor battery life on a linux laptop, and then asks: "Why is battery life on notebooks so poor when using Linux?"
Well, who says it is? The old notebook on which I replaced XP with Ubuntu 8.10 (and then 9.04) has much better battery life under Linux that it had under Windows (plus it periodically would heat up and crash under Windows, but doesn't do that with Ubuntu.) Unlike the author of the story here, I won't generalize from that and say that Ubuntu is better for notebook performance in general than Windows; I personally think at least part of my experience is likely due to an age-related hardware quirk interacting with something Windows--or something else that was installed on Windows--did which was causing atypically poor performance under Windows. What I will say is that comparing Windows and Linux performance on one hardware setup is not a good basis for generalizing about their relative perforamnce for notebook computers in general.
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.
If it's something that technical, I wonder why Remix isn't compiled that way by default? That's way beyond what most users would be capable of figuring out.
Is the user experience that different? Seems strange that Canonical would have overlooked something so obvious. I'm going to give them the benefit of the doubt that something unpleasant happens to the user experience but I have no clue what that could be.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Actually, I expect that more of the people that are paying for Linux support and Linux related services are buying multicore servers than cheap laptops and netbooks.
And I expect that the people paying for Linux support and services are much more important to the people for whom Linux is a business than the people who aren't paying for it. Just because software doesn't have a license fee doesn't mean that it writes and maintains itself for free. People are, in fact, paid to work on Linux, and the money that pays them comes from somewhere, and where that money comes from has an effect on priorities.
Sure, but the approaches that produce lower power consumption and better efficiency with the kind of hardware, applications, and loads that are typical of "big iron" use and the approaches that do so with typical desktop, notebook, or netbook hardware and usage patterns are quite likely very different.
If I understand GP correctly, the problem isn't with FS being journalled - the problem is that when it is, you hit the problem in his point #1 faster.
How will switching to Mac make people think you're not a fag? If anything it'll only reinforce their suspicions.
Actually, default FreeBSD filesystem isn't journaleed - it's using soft updates instead.
On the other hand, NTFS is journalled. So it's not journalling as such - more likely the difference in how it's implemented.
Well, to be complete, you need to run Windows XP and see how the battery life compares. Otherwise you've only got 1/2 a data point.
It is notoriously hard to work with power management features of notebooks, because it is hard to find a really ACPI-compatible BIOS. Most of them are broken in some way, or require undocumented voodoo and magic values to behave. There is really no solution to this unless: a) Manufacturers get their shit together and ship functioning hardware, not hardware that accidentally happens to work under Windows (systemic approach); b) Linux gets more mindshare and those issues get sorted out on a per-device basis (band-aid approach). a) is very unlikely, since shipping functioning hardware brings no obvious reward to the manufacturer. Therefore we can only hope for b).
Note that this is not limited to ACPI. In almost every area, there are hardware products that do not comply with specifications they are supposed to comply with, lie about supported features when probed, have bogus device descriptors, reuse the product ID of a different device, do stupid things when supplied valid commands it doesn't expect, etc.
Those who would give up liberty to obtain working drivers, deserve neither liberty nor working drivers.
Yes Linux does because, in contrast to NTFS, it doesn't have a lazy FS that is so freaking lazy that NTFS always, no matter how empty it is, fragmentates. What am I talking about? -> Spreading data.
Here be signatures
I have plenty of anecdotal evidence (5 laptops, 3 different people) that linux power management is really great. Maybe you just aren't doing it right?
But if poster can take the same laptop, and the same person, with the only difference being the OS that is installed.... maybe that's a bit more empirical than "5 laptops 3 different people"?
That charts do some explanation on how they get that numbers, linking to http://eeepc.asus.com/global/computing.html, where they explain that they use one test (Battery Mark 4.0.1) for measuring battery life in Windows, and a different one in Linux (JEITA Battery Run Time Measuring Method). Essentially, there you are comparing apples with oranges.
That's nonsense. It doesn't explain why designed-for-linux netbooks like the Linux Eee systems perform as poorly as they do.
I would bet that the problem can be largely attributed to 1) vm.swappiness being set too high and (IMO every laptop user should set vm.swappiness = 0 unless they know a higher metric would help their specific operation behavior) 2) ext3 sucks horribly, 3) linux often defaulting to the 'standard' and ignoring/overriding hardware bugs which might be accounted for in the closed drivers (such as with the BIOS), 4) hard drive power management options/defaults are usually not very good and do not account for/override filesystem settings.
There might be something else to it, too. I've personally never had a laptop that got better battery performance in Linux than in Windows; it's always just been Part of the Deal of running Linux to get worse battery life, despite what I've heard others say.
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
I'm running a stock Ubuntu install (except Nvidia drivers) and my battery life is great. The sleep mode works, too. The key to running Linux is using compatible hardware and it works very well. Ubuntu really has made the user experience better than Windows. I'm not saying that Linux offers the same breadth of software but on compatible hardware is really is slick. I was at my brothers and wanted to print a file. I plugged the USB cable in and the selected the printer while printing from the application. No downloading drivers, no loading crapware from a CD, just plug in and print.
"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
Remember ASUS sleeping with Microsoft under the sheets? Google the deal.
Here be signatures
Ubuntu 9.04 - 64bit with 2.6.28-15 is.
Turn off periodic SMART status checking (on some drives this spins it up).
Sigh. You had me going with that one. That's the only thing I didn't think of when I tried diagnosing why I can't my Thinkpad to keep my Seagate drive spun down. Even with everything off (no syslog, cron, etc.), the little fucker still insists on spinning back up after a few seconds.
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
Nice find. It would seem to me that the vendor has failed to configure Linux properly. As shown in above posts, there is nothing inherent to Linux that mandates a high power drain. I also note that the difference in battery life, while significant, doesn't approach the difference stated in TFA. It could be that Asus is NOT using the "tickless" optimization mentioned in posts above.
So - it is probably safe to say that Linux comes out on the short end of the stick due to lack of hardware (vendor) support.
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
I get ~6 hours on Ubuntu 9.04. Beauty is, the battery remembers (I don't know how) to start charging when below 60% and stop charging at 98%. This is the setting I did on Thinkvantage Power Manager under Vista.
"I loaded the movies into a RAM disk and set the hard drive to power down, shut off syslog, and removed the DVD drive completely."
Aren't full-length DVDs something on the order of 8GB? How much RAM does your laptop have?
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).
Hey, I'm working on the "Hot Flames" achievement here by getting a "+5 Flamebait".
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
Why? It's exactly the same problem as health care. Kids (and parents) who eat their way into a diabetes-induced amputation, costing more in health care than it would cost to provide basic services to a dozen other families, aren't a bit different than kids (and parents) who slack their way through school and become parasites on every other system. What on earth makes you think that more of a Nanny State is going to produce kids who are more responsible for their own lives? It's all part of the same wider cultural problem. And government policies that amount to nothing more than just raising taxes (more!) on the productive people to increase the number of Nannies aimed at the non-productive people are all of a kind.
Whether it's a national health care, the kid has health insurance or not would probably make about zero difference for someone stupid enough to do that in the first place. And if it's a kid, WTF is child protection services when you need them... what's wrong with Americans, but I digress. I can only tell you from experience that people aren't getting themselves sick and injured for the privilege of having a free treatment. So it's really about getting away with you paying less for your lower risk compared to their higher risk, but it leads to the "let's inspect your life" game for both of you.
Got lung cancer? You a smoker? No, never you say. Lord help you if they dig up a picture from 20 years ago when you were 16 and tried it to be cool. Or if you got back problems, who's going to know if you just have or if you tried lifting that 50kg whatever all by yourself? 24/7 video surveilance? Everything becomes a game of being measured and prodded and poked to find something in your history so they can avoid paying you. And if you got any kind of medical history where they think you will or might need expensive treatment in the future, watch your premium skyrocket and noone else will insure you. Even if it's a completely natural condition that you can't reasonably be blamed for inflicting upon yourself. There's many ways you can be screwed or treated like a fraudster without being to blame.
Even once you get past that, they're only likely to cover the cheapest treatment at the hospital cutting the most corners. I suppose you could win a little, but I don't think much considering the overhead. You're probably paying as much or more to have a good insurance that gets you into good hospitals as footing the universal healthcare would. Here it's like if you need an amputation, you get it without a whole insurance company in your way. It's not like people keep coming back for more anyways. The things that you are to look out for are not the treatments, it's fraud with these:
1) Disabilities pension
2) Drugs for resale
3) Fake sick leave
All three often more than willingly helped by corrupt doctors and something to look just as much out for in the private health sector.
Live today, because you never know what tomorrow brings
ever heard of power management?
Have you heard of reading the summary?
it's on by default in windows.
It's off by default in most Slashdot readers.
maybe you should figure out what your settings are for linux?
Maybe you should learn how to turn that setting on before posting?
I have found that if your kernel wasn't compiled with the correct CPU drivers, the CPU might not be speed stepping. If you are using gnome you can use the gnome CPU applet to see the actual CPU speed. In my case, (HP DV1000, Pentium M 1.73 CPU) with ubuntu Hardy, the CPU steps fine, but having the "correct" CPU voltage and speed values hard coded on the OS kernel prevents me from underclocking and undervolting the laptop under linux (without compiling a custom kernel), which is easily done in windows with software such as Rightmark Clock Utility. So my battery lasts 1:30 hours with Ubuntu and almost 3 hours on XP. Guess which I use the most for school even though I strongly prefer FOSS?
Greetings, programs!
I didn't have to do anything special and Ubuntu works quite well on my EEE laptop. The battery life might be short but not by any noticeable amount.
Watch as this trollfeederfeederfeederer realizes what he just d.... aw crap :(
Making one of your products look better than another of your products doesn't really make any of your products look worse...
But they would have no reason to falsely claim that one of their products was worse than it actually is. Which is the point I was making and you failed to address. This would be like Ford falsely claiming that one of it's cars has 25% less gas mileage than it really does which would make absolutely no sense to do. Secondly, yes it would make it look worse in the eyes of someone who was shopping for a laptop with a keen eye for the battery life.
Doesn't matter.
It's X.
You didn't know that? Obvious.
deleting the extra space after periods so i can stay relevant, yeah.
that's a good set of points you make skull. have you considered following your own advice? (http://slashdot.org/comments.pl?sid=1229581&cid=27915343)
i.e. you should also read the convo.
i'll spell it out for since i don't expect you to do any reading. linux power management doesn't work that well because most systems are not fully ACPI compliant and cheat using their windows-only drivers.
Battery life and wireless support are the two main reasons I switched from Linux to Mac, for notebook use anyway.
-fb Everything not expressly forbidden is now mandatory.
Correct, hardware manufacturers do. Windows doesn't. Presumably, Linux should be trying to optimize for hardware, too, right?
Granted, there are some things somewhat out of their control, like ATI or nVidia drivers.
But on the whole, it doesn't really seem like most "Linux geeks" are particularly interested in things like battery life (or, as someone posted in the xkcd comic, full screen flash video... which I realize is also at least partially an Adobe issue...). Self-included; my old laptop running Ubuntu 9.04 essentially has no battery, it dies the moment the AC adapter is unplugged. And I don't particularly care, hehe.
I have an EEE and on an HP DV5, and I get about the same batter life under Windows and Ubuntu, both with the default installations.
I run Ubuntu 9.04 (64 bit) on a W500 and get > 2 hrs battery life with the standard battery (not the extended life). I have not done any specific configuration tweaking to try and extend battery life.
I haven't compared battery meters between Linux and Windows, but I've long suspected the over-estimation issue is a result of modern batteries themselves. A characteristic of earlier batteries was that the output voltage would drop as the battery discharged. One could get a fairly reliable measure of battery charge by simply putting a voltmeter across the battery terminals. (This works well with the lead-acid battery in your car, for example).
An ideal battery, however, should provide a constant output voltage, and successive generations of batteries have improved on this. If you imagine a graph of output voltage over time, modern batteries maintain a fairly horizontal line until very close the end of their charge, at which point the output voltage falls off precipitously.
This presents a new challenge. How do you determine the charge level of a battery when it "appears" to have a good charge right until the end? External measurement won't suffice, you need a "smart" battery that can provide information about its internal state. I think this is what the InfoLithium® battery in my Sony camera is supposed to do.
In Windows, the default warning times can be a killer. I've seen Windows laptops die with no warning at all, only to have the warning message appear after they're plugged in and powered back on. On some laptops I've had to set the warning time to as much as 25 minutes to ensure enough time to get an adapter plugged in before it dies.
Why is an out-of-the-box XP machine performing better than an out-of-the-box Linux machine?
It isn't.
The Linux community shouldn't be saying "try this" or "tweak that" or "install this device driver" or "switch your hardware"...
Actually, "switch your hardware" is a reasonable suggestion. If you try to run software on hardware that's not compatible with it, it won't work. That's also true for Windows and OS X.
This is a critical problem with the topic.
I have anecdotal evidence similar to the parent's post as well.
http://www.maxineudall.com/2010/02/should-economists-be-sued-for-malpractice.html
In that prior thread (wow, you had to reach far back to find an example that was even close), I was responding directly to the point raised in the parent - which I did read. Whether I read the preceding conversation or not I can no longer recall - I likely did, but it's irrelevant to the point.
In your post here, you replied directly to the summary and your reply ignored that he pointed out having tried all of the configuring and tweaking he could find to do.
So what conversation should I have read? And how would it have revealed this information to me:
i'll spell it out for since i don't expect you to do any reading. linux power management doesn't work that well because most systems are not fully ACPI compliant and cheat using their windows-only drivers.
which was mentioned neither in the summary, nor in your reply to it. In case you've forgotten, this is what you wrote:
ever heard of power management? it's on by default in windows. maybe you should figure out what your settings are for linux?
I don't see ACPI, Windows drivers cheats, or anything else mentioned in that post - which comprises the extent of the conversation you allege I did not read.
You posted a shot from the hip in the form of a mildly snarky comment, and got called on it. Life goes on.
Really? Battery life on my desktop sucks. It dies as soon as I remove the power cord.
You must be doing something wrong then. I've got a couple of old desktops whose batteries are still not drained after going for more than 10 years on their original charge!
So post instructions on how to do it on the LKML and try to inform the devs of this problem...
Did you look into pdflush? In particular dirty_writeback_centisecs? lsof, iostat, vmstat, and strace in a process of elimination are useful as well. It is too bad linux (I am assuming you are on linux) does not have something like dtrace or at least fs_usage. Did you do the other stuff listed above? In particular you could have some stupid process that writes-out its config at something insane like once a second. There was some notorious Seagate firmware for a while too, but not on the small drives as far as I know. Good luck.
Are you really saying that 3 hours is a "good" thing?
I would consider it poor. (except for some really low-end stuff)
It's incredibly hard to say because the summary doesn't provide enough detail in and of itself to diagnose the problem (e.g. which graphics card, which chipset, which drivers are being used, which version of Ubuntu and so on). The most likely explanation is that hardware is being left on in Linux that other OSes are powering down when on battery. Examples of this:
As you can a myriad of reasons and not nearly enough information to whittle down the cause. Further how do you know each OS is using the same defaults? It could be that Windows says you are running out of battery later than Linux does (I'd imagine that this sort of thing could only account for 10 minutes difference to actual empty battery though) or the display is defaulting to a different brightness - it could be that lots of little things are adding up to the major difference.
A few years ago I had access to a Thinkpad T60 and it would draw two watts less power under Windows XP than under Ubuntu Gutsy. That doesn't mean things don't change over time but nor does it mean that people aren't seeing real problems now. If you know how to constructively help, things can get progressively better on your system but it can take some time and you need to know how to track these things down. Tools like powertop help and developers have been putting together good power management practices for Linux guides. However in all honesty posting to Slashdot is unlikely to help you obtain a solution (and indeed there is no guarantee of a solution even over a long period of time).
It was very difficult to decide whether to mod the parent funny, or to "Whoosh!" you.
Doubly difficult since parent was already +4 Funny and you're an AC.
Most laptops come with a windows tool that slows the DVD player down, maybe that's a reason. Another thing you can try is to just let it on till it goes off because it's really empty. Maybe the indicator is broken, and it is not using more power.
The Adobe Linux flash devs have seen that comic too and reckon the issue with Linux full screen flash performance is down to graphics card driver capabilities and the difficulty in discovering them.
I own a W500 and use Arch Linux on it. At first I too was disappointed at the short battery life, when I found a BIOS option to enable extra powersaving.
I now enjoy 3+ hours of battery life under normal work conditions.
LOL. I do appreciate the followup, so here's what I discovered since my last post.
I'm using FreeBSD, and have the same or similar tools (dtrace included), but I've never been able to track the problem down without losing interest and patience.
Turns out that stopping cron and syslogd wasn't enough. I modified my mounts to use the noatime option (which worked until I started X), so then I reconfigured /var and /tmp as md (memory) devices and ...
Now my drive stays spun down!
Fucking hell. I use my notebook far more than any desktop system, and I've been putting up with an overly "warm" keyboard and unecessarily spinning drive for years. The CPU I can throttle or adjust dynamically, but the drive? That required me reading a random post on Slashdot to fix.
Can't thank you enough!
I'll have to look into the Firefox issues you mentioned, of course. More importantly, I'll have to find a solution to having the contents of /var disappearing with every boot.
This reeks of Compiz. If compiz is in use, the GPU may be stepping up to it's max 3D mode clock speed, especially if it is under load. CPU scaling may also be tipping over a threshold.
I'd put some money on this.
The dude also says he is playing a DVD, I would hazard a guess that the DVD software he is chewing more CPU or interfering with power states differently on linux.
From experience desktop effects will chew your battery even if your doing low CPU usage tasks like reading web sites. Your just moving app windows around but this is enough to push your hardware over scaling thresholds and use more power.
A smaller effect my difference in some power saving behaviour. Windows XP more agressively caches data to memory for reducing hard disk access, more likely resulting in HDD spin down more often depending on the timeout. Linux is always very frugal with making use of memory, even if you have a metric assload of ram.
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
Sure! Nice Windows RAM disk app.
Now get the hard drive to spin down and stay that way while watching a two-hour movie.
+5 Inciteful
Samsung took back my unlocked bootloader because Google wants me to rent movies. They're both evil.
Not sure if somebody above has said it yet, but you need to install powertop and run it as root.
That'll increase battery performance.
.
So maybe it's time for both kernel developers and distribution packagers to focus a little bit more on which hardware users are buying. Which is not multi (4+) core servers, but rather cheap laptops and netbooks.
Someone's buying those, and it's the people with the money. Con Kolivas ran into the same problem years and years ago.
No, it's not the same problem. Congenital birth defects, accidents, car accidents, Breast Cancer, Colon Cancer, Leukemia, Prostate Cancer, Lou Gehrig's Disease, Alzheimers, Asthma, Muscular Dystrophy, Post Traumatic Stress Disorder, Meningitis, physical assaults, Hepatitis, Influenza, Pneumonia, etc... etc...
There are millions of people with billions of dollars in health care expenses that didn't do anything wrong, and many of them are too young, too old, or too sick to work. Many others are able to work, but they can't get private health insurance because of their pre-existing conditions. There are legitimate reasons to criticize the current health plans under consideration, but you're a fool if you think lifestyle, rather than luck, is "insurance" against most expensive ailments.
Have you tried to spend even more time (assuming you did spend some) on www.lesswatts.org?
All the tricks are there, even checking for tickless kernel, timer interrupts. Intels 'powertop' utility is my best friend with Linux power management.
So maybe it's time for both kernel developers and distribution packagers to focus a little bit more on which hardware users are buying.
Which is not multi (4+) core servers, but rather cheap laptops and netbooks.
And, anyway, lower power consumption and better efficiency will probably also benefit the "big iron".
Chrome OS to the rescue.
Sadly, I suspect it will be the only rescue.
Did you enable frequency scaling? Under KDE3.5 I use kpowersave. There's a frequency scaling applet under GNOME as well. I just can't remember the name at the moment.
They did not make their own products look any worse than disclosing battery life for Windows and Linux side by side. Same machine, two numbers. All it did is make "battery aware customers" want XP, which, given Microsoft history of lobbying and what not, probably is their doing as well.
The problem is that these paragraphs are directly contradictory. If your hardware is homogenous, then yes, it makes sense to test like that. If, however, you've got to handle a poorly-implemented badly-designed hardware spec, where you don't know if "pulling the pins high" is actually going to do that or, for instance, overwrite something in a random register that could end up bricking the device when someone else runs your test on a version of the model where the manufacturer thoughtfully didn't bump the hardware revision, then treading a little more carefully is indicated.
Do we know that what you suggest has even been thought about? No, not at all. Not even for the cases where it's blatantly obvious that it would be safe. At least, I (as a moderately interested bystander) don't have the confidence that it's been done, but it's only in the last couple of years that sleep mode has worked at all, in my practical experience. I'm happy if energy efficiency is the *next* thing they look at, not annoyed that they haven't done so already.
Reality is the ultimate Rorschach.
Windows has OEM drivers which are [by design] tailored for hardware. Thinkpads, for example, install their own power management service and driver. Evidently, these help battery life. Newer ATI graphic card drivers install with "PowerPlay" thing which idles GPU when not used. Without such drivers OS has no idea how to manage hardware except standard I/O and VESA for graphics output, neither of which are very PM-aware.
I've used Linux for years on a variety of laptops, and generally with recent releases (over the past 5-6 years) I have managed to get very good battery life out of Linux.
Enabling frequency scaling helps, and making sure you don't have processes sucking the processor (and thus forcing the processor to high-performance mode) will certainly help. Dimming the display also helps - most modern distributions should do this automatically.
I've got 3 different Dell laptops here that get 2-3 hours off a battery running openSUSE 11.0/11.1. I have a Thinkpad t42p with an extended life battery that I used to use constantly and I'd get 3-3.5 hours out of that.
If you're only getting 45 minutes out of a battery on Linux, either something's not been configured correctly in your distribution or you've got something driving processor utilization up.
Insanity is a gradual process; don't rush it.
You mean with Linux and OpenGL my laptop can actually compost stuff? Cool! Where exactly do I shove in the scraps from my in-flight meal to get it started?
You are mixing terms all over. BIOS is software too, just very pervasive and persistent software. But it is the same kind of code that what you refer to as "software power management" is. Also, BIOS usually only does rudimentary power management, and since two conflicting procedures "power managing" the same hardware through the same port would be a bad idea, one of these is usually disabled - usually BIOS, it being simpler, so that the other one - the more advanced (hopefully, see OP :-) OS power management - can assume the "managing" role. Simplified explanation, but that is how it works. The advantage is again - refined control, including user control. BIOS is not only a black box, it also is a very stoneage UI - Once you set up PM in BIOS, it takes a restart and re-fiddling with its settings to change the PM again. ACPI is what should be used as a PM interface, but in reality it is usually a mix of ACPI and BIOS routines. This is where my knowledge stops unfortunately.
Right, hopefully this will sink in and dispell a few other myths.
One of the ways to get increased battery life is to use PulseAudio. Right, now that some of you are doing the characteristic snorting and thinking up a derisive comment for a reply I'll explain.
Glitch Free mode in PulseAudio is a new technique that disables the audio hardware interrupts and uses kernel-based timers to feed data into the sound card. It's called "glitch free" because if it detects an underrun it will automatically decrease the time it waits before it wakes up again. This has the effect of reducing the power efficiency at the expense of lowering the likelihood of another underrun occurring. By disabling the interrupt and using higher latencies you can massively reduce the CPU wakups and thus increase battery life.
Using this approach you can get much better power efficiency, but it doesn't end there. Applications have to be written with the concept of "latency is good" rather than the "we must have small latency" mindset that is currently quite popular (although quite often totally incorrect) Take a media player for example. You can decode 10seconds of audio and pump it into a large latency system pretty damn quickly (realtime streaming doesn't apply here but buffering is still needed there anyway).
Yes, this approach is new and yes it pushes the ALSA drivers to their limit and exposed many bugs (no other ALSA application has pushed the drivers as hard as PulseAudio and such low level bugs are therefore to be expected). This has lead to some people to be critical of PulseAudio but such people will eventually eat their words (or rather they will change history and claim they never said it was a bad idea, just that it wasn't ready yet etc. etc.).
While I don't want to comment incorrectly, I beleive the default Ubuntu setup disables PA glitch free mode by default. Perhaps you should turn it on?
I'm very happy to hear about your success. I'm a big fan of FreeBSD as well.
Read the syncer man page, there are sysctls that you can tweak to slow down flushing the pagecache so your disk will not spin up as often. If your laptop is very stable you might not worry so much about a panic. The battery should give you enough time for a sync or halt in case of a power outage.
On a laptop, I find I hardly ever care about the stuff in /var after a reboot. Using md was clever.
Judging by the comments here, the situation with Linux power efficiency sounds like it's more or less where printing was, say, 4-5 years ago. That is, it actually works pretty well and gives you a lot of control, but how you set it up and control it is somewhat obscure.
To be honest, I like to think I'm a pretty hardcore Linux user (exclusively Linux on all my machines since 1997) but even now I haven't really messed with power management beyond figuring out how to change the current CPU frequency from the command prompt when I want to (and making some minor tweaks to the default settings in KDE's battery monitor plasmoid. Well, yes, and making sure my kernel was compiled tickless...). I get 4-5 hours out of the battery in the little netbook that is now my current main computer. Arguably, I ought to be able to get that up to 6-7 hours with some agressive modification and obvious things like "remember to turn off bluetooth and wifi when not in use", but why bother? It still beats the crap out of the 1.5 hours I got out of the now-old gigantic Compaq laptop and gives me plenty of off-the-wire time. ("Get off my lawn", etc...)
Anyway, the point is that it looks like there is a decent amount of power-management capability already existing in Linux systems, and what's missing is a simple way to make sure it's turned on and configured the way you want it.
Some links to projects trying to make the "CUPS" of Power Management would be appreciated if anyone knows of any...
Hacker Public Radio is our Friend
There's a diversity of equipment out there that owning a single laptop can't capture. Consumers generally can't accurately make a conclusion about the state of Linux power support; my laptop works equally well on Windows and Ubuntu yet I won't start declaring Ubuntu power management just as good as Windows.
But there's more to this story. Consumers also don't have equipment to measure power demand. Time remaining can be misreported, so at the very least use wall-clocks. It's much better to measure power draw, but your kill-a-watt won't cut it, since laptops generally alter their behavior on AC. What you want is to instrument the battery itself. Not easily done without risking a fire.
I Browse at +4 Flamebait
Open Source Sysadmin
You basically need to become proficient in all those startup scripts. They are doing all the job, really. Okay, most of it. I did it on my laptop, Thinkpad T43. Let me see... Here it is: I edited the /etc/rc.local file which as far as I remember is executed every time the runlevel changes. More on it all - Google.
A lot of systems have broken ACPI implementations... Broken in that they don't comply with Intel's documented spec for ACPI, they follow microsoft's specs instead.
Depending on the hardware, linux can have better battery life than windows. My experiences have varied massively depending on the machine.
OSX achieves good battery life because the hardware and software are designed together, from the brief testing i've done linux on my macbook pro has better battery life than windows but not as good as osx.
http://spamdecoy.net - free throwaway anonymous email - avoid spam!
...and I'm up to 3.5h of battery life (battery at 90% health) by using the powertop utility (try it!). Another great tip is that if you have an ATI card and are using the open source radeon driver with it, inserting the line
Option "DynamicClocks" "true"
into your "device" section in your xorg.conf makes it draw up to 2 watts less power (a lot in this context).
Good luck!
Have you checked your apmd settings?
by Mike Buddha -- Someday the mountain might get him, but the law never will.
This guy reports 2.5-5 hours of battery depending on which graphics drivers you're running. Maybe there are some more pointers there.
Why is battery life on notebooks so poor when using Linux?
I wish I could tell you, but, like the above W500 owners, I've only ever gotten perfectly competitive battery life on Linux laptops.
Obviously Apple with their X86 hardware and BSD based OS have got it right because the MacBooks last for hours
Their new ones are better, but I have one of the old MacBook Pros from about a year ago which might get you through a feature-length movie if you're lucky. My Linux netbook completely owns my MacBook in terms of power usage--the Mac seems to be converting a lot of it to heat. The netbook will suspend seemingly forever.
Any time you install an OS on some hardware that didn't ship with it, you're taking a chance that it might not work. Vendors try to make their stuff work with Windows, so you'll probably have good luck there, but even vendors ship with specialized OEM versions of Windows. Trying to install Linux or OSX on machine that didn't ship with it, especially if the hardware is new, is going to be interesting. My advice to those not willing to tinker: leave it to the pros and buy a preinstall.
"After settling on Ubuntu I then spent three days trying various hardware tweaks"
I have the same problem anytime I try to do anything involving Linux and hardware, and after years and years of this sort of thing I got fed up and switched back to Mac.
I know Linux is inherently better from a software freedom perspective. I know it has an uphill battle because of limited support from hardware vendors, unlike Windows. I know they're limited by not having control over the hardware like Apple. This is Slashdot heresy, but quite frankly, I DON'T CARE. I want a computer that does the right thing without being asked, without having to spend days searching forums for answers, without having to learn cryptic kernel commands.
Does that mean I should hand in my geek badge and go home? Maybe, but quite frankly, I'd rather spend my time doing geeky things that I want to do, rather than geeky things that my computer forces me to deal with.
Overall from my experience I can tell that Linux (as a whole) extremely poorly optimized for notebooks.
I have spent at least two weeks cleaning my Ubuntu installation to get any decent battery life. I ended up with essentially stripped down Xubuntu installation.
My approach was simple.
1. Run 'top' to see list of process running. Disable unnecessary services while you at it. Uninstall what can be uninstalled easily.
2. Run 'pidstat' to see which processes write too often to disk. Uninstall what can be uninstalled easily.
3. Turn /tmp and /var/* from directories into tmpfs mounts (you should have spare RAM for that, but most modern PC hardware is oversized anyway). That will save a great deal of disk accesses. Note that some /var/* sub-directories have structure and can't be easily turned into tmpfs mount. Experiment a bit in single user mode.
4. Reconfigure syslog to not to write redundant stuff into the log files: disable markers and configure to ignore periodic messages from daemons.
Worst what I have encountered were gnome-power-manager (which writes every 90 seconds to disk state of battery thus preventive hard drive from *ever* going to sleep) and syslog (finding easy to understand manual on discarding messages was major pain).
If you really into notebooks, I can only recommend Apple. Both standard and 3rd party Mac OS X applications were tuned for laptop workflow eons ago. Also Apple picks hardware which is better suited for the notebooks (that's why you will never get in Apple's laptop higher-end CPUs/GPUs which are pretty common in Wintel notebooks).
Go with Linux only if you know how to work in single user mode, know how to install/deinstall software from command line and how to bring the OS from dead (if some tuning attempt went wrong, e.g. putting /var/* onto tmpfs). And be prepared in the end to say goodbye to many bells and whistles. For example my friend has old Toshiba's subnotebook and manages to get out of it 8 hours - but he works exclusively from command line and uses fvwm for his GUI needs.
All hope abandon ye who enter here.
Oddly enough, I did recently experience Windows killing my desktop due to powerdrain. I had been using Ubuntu only for quite some time prior to this install. During regular usage on Windows, I started smelling something like burning plastic. I immediately turned off the computer of course, couldn't find any obvious damage, and went back to regular use in Ubuntu after it cooled down. After leaving the computer on 24 hours a day in Ubuntu for a few days, I booted back into Windows again and, sure enough, more burning plastic smell and the computer crashes.
It turns out that at some point (a long time ago from the looks of it), the fan inside my PSU had snapped and it was no longer spinning. Apparently, I had run it like this in Linux for quite some time with no problems or damage done. However, around an hours use in windows obviously drained more power and overheated the power supply.
In short, Windows did in fact draw too much power on my desktop and cause it to shut down.
Spooooon!!!!!
Sounds like you are simplifying the situation alot. Yes thats how you do power management on tiny microcontrollers, but that has nothing to do with power management on a typical PC.
Video card have ways to stop clocks in certain areas of the chips, this is the main way power is saved, same with CPU's. These devices don't have I/O pins in the same way microcontrollers do, usually all the buses are tri-state and there is no need at all to 'set' something to input or output or high or low, you simply high impedance the whole bus connection.
What you are talking about has nothing to do with programming on modern computers, you can't just tell your video card what pins to set as output and input, you have to talk to it over a bus, and it runs its own firmware/bios that may have calls that make it disable clocks in certain parts of its chips and high empedance certain bus lines etc. Knowing what these commands are and how to talk to chip when the manufacturer doesn't release any details, just a windows binary driver is the whole problem in the first place.
The W500 has two graphics adapters. An underpowered, integrated, intel(?) chipset and a full blown 3D-accelerated ATI one. You need to set your laptop to use the integrated chipset and not the ATI for max power savings.
--Michael
Linux power management is generally poor due to poor drivers.
While the Linux drivers for most hardware devices are very stable due to their open source nature, many are reverse engineered from windows drivers or written from incomplete specs. Also, paid developer time is scarce for this kind of project, so often only core features get included.
The features which get cut are often power management and additional optimisation - the result, you end up with a system that doesn't perform great, and has poor battery life. Not much you can do about it without changing to different hardware.
My experience is not quite as bad, but I will admit that windowsXP tends to best my battery life in ubuntu 9.04 by about 15 to 20 minutes. I'm pretty sure it's about equal to ubuntu in win7, but I know it wasn't as good as ubuntu in vista. This is on an inspiron 1525. Battery life for laptops I have found is usually a bit worse in linux, but I've never heard that it performs as badly as this post. I'm saying it isn't that bad for you...I'm sure it is. Lets face it, stuff breaks in linux all the time. My intel graphics drivers are the PERFECT example of poor/unpredictable performance in linux.
The Linux OS "spoofs" the OS to be WindowsNT by default, not WindowsXP as has been incorrectly stated above -- just look in acconfig.h to see for yourself. Use "Windows 2006" to spoof it as Vista and see if battery life changes. BTW, if you do want to spoof as WindowsXP, the correct string is "Windows 2001" and "Windows 2001 SP2" for Service Pack2. Look in acconfig.h for all the values. You need the quotes when adding this to the kernel command line. Use the string that matches the version of the OS that the OEM provided with the laptop, or try different valid strings from acconfig.h until the device works properly or no error messages appear in dmesg. Also, if the string does not appear in your ACPI BIOS, the BISO will revert to its default, whatever that is. You'll need to disassemble the ACPI BIOS to determine the specific values permitted, but assume that at least the OS supplied by the OEM is valid.
"I believe in Karma. That means I can do bad things to people all day long and I assume they deserve it." : Dogbert
There are legitimate reasons to criticize the current health plans under consideration
That's putting it mildly.
There are millions of people with billions of dollars in health care expenses that didn't do anything wrong
Of course. That's what insurance is for: the big, catastrophic stuff. Just like car insurance, which you don't use for your oil changes. Or the unemployment insurance that you and your employer pay into while you're working - to help with unexpected circumstances. You don't use that plan to pay for continual, normal needs like food and rent. And there's no reason that health insurance should pay for a check-up, either - and imagine how much less it would cost if it wasn't really just a savings plan to make a visit to the office "cost" you $20 instead of $100.
A health savings account should, perhaps. But insurance? You insure against the possibility of something happening. The need for routine medical care is a certainty. So let's talk about why that routine care is so expensive. One answer: lawyers. Caprcious, predatory, lottery-sized law suits, making oily weasles like John Edwards multi-millionaires. And that industry (the trial-lawyer industry) has forced typical doctors to pay six-figure annual insurance premiums, and to practice hideously expensive defensive medicine, throwing untold billions of dollars of pointless tests, equipment, and treatments at patients just to fend off the legal parasites and opportunists.
too sick
Sure enough. My dad had to finally quit working because of ALS (Lou Gehrig's disease). He elected not to undergo long, wretched treatments and circumstances costing untold tens or hundreds of thousands of dollars over time, with the same outcome - only more miserable - either way. So I got to watch him die in front of my eyes, unable to breath, and refusing a trachiotomy. Hell of thing - hard for me to imagine, even today. He had a doctorate in health administration, and was a vice president of a huge health insurance company. It wasn't about the cash, it was about the waste and the misery, and about his personal dignity. He used insurance to cover some immediate costs during his decline, and then drew the line at the point of his choosing. Don't lecture me about sick people who didn't do anything wrong.
Don't disappoint your bird dog. Go to the range.
I've found Flash-based sites such as Youtube to be quite effective at burning the battery. I know this because when I used to run Vista on my laptop, I could watch quite a lot of online vids before draining the battery. Not as long as if I was just simply browsing non-video content, but still a lot longer than the same streaming in Linux.
Now of course, the CPU usage by the Flash plugin is ridiculous in Linux compared to Windows, but at least I had a source for my power problem. No real way to fix it either except to attempt to bypass Flash by sending the URL stream to VLC or whatever, or just put up with it.
You get more hours with Windows in order to compensate the use of the anti virus, the chance to loose your files from time to time, the time you spend to install all the upgrades, time to read the licenses...
Kinda fair to me.
To reduce -a lot- the disk activity, mount all your FS with the 'noatime,nodiratime' options in fstab.
This will prevent Linux to update the files access time when they are read.
Slashdot, fix the reply notifications... You won't get away with it...
Especially when the product you're making look better is a product someone's getting paid for.
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.
After reading though these comments, all I can think is - yeah, here's an issue where default Linux should do a better job - one on par, at least, with the latest Windows/Mac OS.
Optimize your default distros so us average schmucks don't need to fiddle around under the hood. I have tried repeatedly to use Linux on my netbook - and even setting battery life aside it's always a colossal hassle - ending up (after many steps) with advice about recompiling the kernel, etc.
You really believe competition is good, right? And I'm sure you're fair minded enough to admit that you are not going to win every usability feature just kinda because, right?
Get power usage nailed down tight. It will payoff HUGE in the brave new mobile world.
Sounds like you need a UPS. For the cost of a decent Netbook, you're desktop can easily rival many notebooks in battery life. Try plugging the modem and router into it too. Did you know that your DSL will still work during a power outage?
If you're trying to compare the battery life while using different OS's, like what we're trying to do now - then using different machines is totally worthless as there are just too many variables.
Linux should be trying to optimize for hardware, too, right?
I think you misunderstand the problem. ACPI is the power management standard that all the manufacturers use. It's not a particularly good standard in the first place, and in the second place, most manufacturers make horribly broken non-spec ACPI interfaces. They fail to document them adequately if at all. They then provide customized windows drivers for that broken implementation.
Kernel devs are constantly tweaking the ACPI drivers for all the different hardware out there, but they're at a stark disadvantage.
But on the whole, it doesn't really seem like most "Linux geeks" are particularly interested in things like battery life
Between 2.6.29 and 2.6.30, a span of 78 days saw 7 commits to the ACPI subsystem, for a total of about 800 lines of code added. That's pretty average on a size-per-size basis across the rest of the kernel, and normal for the overall upward trend in kernel development speed. So it seems that just as many "linux geeks" (which i am interepreting strictly to mean kernel developers) care about battery life as care about any other drivers short of network, sound and v4l.
(or, as someone posted in the xkcd comic, full screen flash video... which I realize is also at least partially an Adobe issue..
comics are reliable sources of information aren't they. it is ENTIRELY an adobe issue, however fullscreen flash video has worked fine on linux for 3 or 4 years now.
This comment is fully compliant with RFC 527.
http://www.thinkwiki.org/wiki/How_to_reduce_power_consumption http://www.lesswatts.org/projects/powertop
But, 5 years ago I had a Asus s5n, i had gentoo and fedora instaled, and the battery lasted more than on windows (I had some tweaks for saving battery then). Same with my current Dell D630 on Ubuntu (default)... so Battery life on linux as always worked well for me
Hence, they're fully aware of any power saving tricks the hardware may provide.
The linux developer(s) may or may not have had that level of support, and many of the drivers have been written without it, some even reverse engineered. Getting the driver to work reliably *at all* was quite likely more relevant than saving power in many cases.
It could simply be one driver in particular chewing the shit out of your battery life, could be all of them...
I run: Windows, OS X, Linux, FreeBSD. Just because you have a hammer, doesn't mean everything is a nail.
This is not my expirience, at work the whole team has an identical laptop (dell latitude 800), the only difference being ofcourse that i'm using linux (ubuntu) while they are all on windows. Now, they are always the first to reach for their powercables while i'm still good.
Try these things: /etc/laptop-mode/conf.d - it contains a bunch of config files, you can get a lot of benefit out of those.
* configure the power manager
* install powertop and check out some of the suggestions it makes
* check out
Sure, by default you probably could get worse battery life compared to windows, and why isn't this done correctly to begin with yadda yadda... it is there, you can fiddle around with it, which for me is good enough at the moment. i'm sure one distro or another will finally get around it and make decent default settings. A year ago, suspend wans't working on my dell either, it does now, and does it very well. You can't tackle everything at once.
Also, don't forget that 'Independent tests show that Red Hat Linux pulls as much as 12% less power than Windows 2008 on identical hardware'
On a long enough timeline, the survival rate for everyone drops to zero.
You talk absolutely utter rubbish. Just because you don't know of the existance of something, doesn't mean it doesn't exist, such as differences in the vista vs win7 underlying kernel code, like cpu addressing methods or locking primitives. How ignorant you must be to assume that something can't exist without you knowing about it. Maybe I'll just start calling Uranus "Neptune" because I don't know about the differences between the two planets.
Maybe in future you could try posting about things you know about, rather than posting about things you plain don't, it might be a nice experience for us all.
The revolution will not be televised... but it will have a page on Wikipedia
"Maybe you should invest in a ne button cell"
Maybe you should invest in a new 'w' button?
The revolution will not be televised... but it will have a page on Wikipedia
Of course. That's what insurance is for: the big, catastrophic stuff.
Except that many people with the big problems either can't afford insurance, can't get insurance due to pre-existing conditions, or hit their lifetime maximum benefits cap and get dropped.
I had a friend who developed stomach cancer and was unable to continue working. He lost his job and his insurance coverage and died a few months later. One of my cousins developed complications early in her pregnancy that put her on bed rest for the remainder of the pregnancy. She lost her job and her insurance coverage too. In both cases, they ended up covered by Medicaid - the government - because commercial insurance failed them. Another cousin develops kidney stones frequently and has accrued a lifetime's worth of medical debt getting care for it. He can't get insurance that will cover his kidney stones because they're a pre-existing condition, so he has to pay out of pocket for everything - like $12,000 for one day in the hospital.
I'm sorry for your father's suffering, and your loss.
You must be having some hardware compatibility issues. I dual boot Windows XP with an out-of-the-box Ubuntu Hardy installation (newer versions are said to have even better power management), and my battery life under Linux is on par with or better than under Windows XP. Measured battery life, that is, not the overly-optimistic estimate by windows' MIBL (Meaningless Indicator of Battery Life).
The only thing I changed in Linux is disabling the desktop effects but that's only fair; windows XP doesn't have them, and enabling them in Vista when running on battery is said to drain the battery in no time. Oh yeah, I've always been using the proprietary video drivers (in my case ATI); there are conflicting reports on whether this is good or bad for battery life.
I schmell WOOSH.
Note: I was 13 when I wrote most of this. Take with several grains of salt.
Try flipping the switch from "magic" to "more magic". It's not safe to leave it in the wrong position.
Slashdot: where don knuth is an idiot because he cant grasp the awesome power of php
Maybe they are incompetent with Linux. Ironically, just killing the "powermonitor" program (showed the current battery status) would nearly double my EEE's battery life. That program sucked down lots of CPU power. It appears to be fixed in a recent update, or maybe I fixed it myself. Can't remember.
There are probably a lot of things they could have done to improve battery life in Linux. ...and don't get me started on the security problems.
> Sigs are like bumperstickers. Once in a while they are amusing, but usually they are irrelevant and irritating.
That would make an excellent sig or bumpersticker.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
If Windows works better for you, use it. Use whatever OS makes you happy. If you want to run Linux on a PC designed for Windows, try a live disk first. If it doesn't work how you like it to, consider returning the laptop. I have no problems with battery life on my Dell.
I know the "never assume" thing in IT, but here, I do assume that
...the dual core CPU reduces speed when idle...
means that he is NOT running BOINC or other numbers-crunching software...
No it doesn't, it means the CPU reduces clock speed when idle. If BOINC or other number crunching app is running, then his CPU isn't really going to be idle. If the CPU is never idle, it will never reduce clock speed - there's no contradiction.
"Necessity is the plea for every infringement of human freedom. It is the argument of tyrants; it is the creed of slaves
I've a Dell 1420 running Ubuntu 9.04 and I still get 4.5 hours. It's an Intel duo with the optional 9 cell battery - 6 cell was standard.
Thank a veteran -- George
If the disk is powered off for many minutes (for example ten minutes) then the savings compared to the cost of spin up will be substantial (it looks like the pay off starts at around 10 seconds after the hard disk has been put to sleep if you read what is written in Extending Battery Life with Laptop Mode). It may even be possible to sleep the disk for longer if everything the user needs is cached (e.g. listening to music sequentially with a big buffer). The killer is that all all those spin ups and spin downs cause increased wear and tear. As such the problem is knowing when it is safe to spin the disk down such that it won't be immediately spun back up again (this may be solvable by forcing a long writeback time at the risk of bigger data loss). See laptop-mode.txt for some examples.
awesome and very very true to form post. Ive been a linux/Unix user since 1996. the same trend continues. I still really like Linux, but I'm a programmer with LOTS of patience. ;)
with Ubuntu 9.04, I get almost the same amount of battery life when compared to Vista. Just a thought that all windows has to do is call particular API's provided by the OEM to make power adjustments such as processing speeds, fan speeds and ..... If the same information is available to any Linux developer, Linux could provide the same features too...... so its nothing innovative that M$ is doing in Win 7, its just implemented the usage of API's that it got hold of long before they were/weren't made Public.
oh freakin another third party app to download and use!! if only there was a trusted repository of all supported apps and a single app to install any apps...... where can I find it????????
and observe how, unfortunately, XP consistently outperforms Linux :(
I went through the first 10 entries which support both OS's and found 8 were exactly the same and two were longer under Windows XP. Is that what you call "Consistently outperforming"?
and observe how, unfortunately, XP consistently outperforms Linux :(
I went through the first 10 entries which support both OS's and found 8 were exactly the same and two were longer under Windows XP. Is that what you call "Consistently outperforming"?
I take you know what they say about half truths. But just in case you're interested in the whole truth, then here it is:
Out of the 28 machines that are listed in http://event.asus.com/eeepc/comparison/eeepc_comparison.htm, there are exactly 22 that have both a Linux and XP configuration; the remaining 6 machines are either exclusively Linux, or exclusively XP, which means their battery life under the two OSes can't be compared.
From within the 22 machines that can be compared, 11 (=50%) have longer battery life under XP, and 11 have exactly the same battery life under both OSes.
So yes. This is what I call consistently outperforming.
The tickless/dynticks Linux kernel patches first appeared in 2.6.21 for the x86 platform. amd64 tickless patches appeared a bit later in 2.6.24. It isn't just a matter of changing the HZ either - it looks at what timers are set to go off and idles until the soonest timer is set to go off or an interrupt arrives rather than firing wakeup events and then realising there is nothing to do (so it's not just switching between fixed frequencies).
There may have been issues using tickless kernels with virtualisation solutions but that might have been when using tickless kernels as hosts rather than guests (it's not something I've looked at) and in all likelihood the problem has been solved by now.
Thanks. I haven't looked at the graphics cards in all those, but from some of the other posts, it appears that the ATI cards have bugs and that, interestingly, only MS and ATI know what they are and they do not document them. It would be interesting to see if those which are slower use those graphic chipsets.
+5 Insightful...I'm proud and saddened at the same time.
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
ChromeOS is Linux.
Maybe Computers will never be as intelligent as Humans.
For sure they won't ever become so stupid. [VR-1988]
I know.
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so many have pushed linux on n00bs claiming its ready for mainstream. these folks have done such a disservice to both the os and the folks they hoisted this upon. until such basics are worked out, its just not ready for grandma
Not in India, it won't. When power goes out, the Internet connection dies too. I know because we have a generator and while the modem and router stay up, the DSL connection dies. Airtel FTL.
My laptop gets at least 30min more battery on my Gentoo build than on XP.