OS Mobility Explored

by Jarred Walton on September 21, 2009 6:00 PM EST

Conclusion: Round 3?

After looking at the initial Internet battery life results from both tests, one thing is abundantly clear: using live websites with variable content isn't the best way of doing things. One of our original test websites appears to have become less strenuous during the past month or so (perhaps one less Flash ad is showing), and there's always a risk of radically different results if/when a site undergoes a redesign. As much as it pains us to say this, we have to consider all our Internet battery life results suspect at this point. Worst-case, they may be off by as much as 10%.

Going forward, we are working to create some test webpages where the content will be strictly controlled - i.e., identical between test runs. We expect there will always be some slight variation between test runs, but the present variation of up to 10% in some cases is far too high. We could run each test half a dozen times and take the median result, or throw out the high and low scores and average the remaining results. However, running even two tests on each laptop for each test configuration can rapidly result in several weeks of testing and we certainly don't want to triple the number repetitions for each test when they can take several hours to complete.

At any rate, we have started testing with a third set of websites, and hopefully the results will remain consistent for all OSes - and web browsers. We should probably mention that the results in those browser battery life tests are also suspect at this point. We completed those tests several weeks ago, and at the time the results between test runs appeared to be relatively consistent, but we're no longer even 90% confident in those results. We will follow up once we have confirmed our latest testing procedure. Our plan is to start with Windows Vista, perform several test runs on each laptop, confirm that the results are consistent - i.e. no more than 2-3% variation between test runs for a given power profile - and then retest the other operating systems. Once we have tested Windows XP, Win7, and Ubuntu we will reinstall Vista and repeat the tests one last time to confirm that there has been no variation over the course of a couple weeks of testing (or however long it takes). Then we'll think about looking at more browser battery life tests.

Unlike the Internet battery life results, we can discuss DVD battery life results with relative confidence. We use the same DVD, and variations between test runs have always been consistent. We plug in a set of headphones and use Windows Media Player for the DVD playback test. Windows 7 was clearly the winner in this particular test on the Gateway NV52, beating Windows XP by around 6% and Windows Vista by 22%. Again, however, changing to a different platform muddies the waters. On the Gateway NV58, Windows Vista is clearly in last place; XP offers about 21% more battery life and Win7 offers 18% better battery life. That said, this time Windows XP beats Windows 7 by around 3%.

We also said that we weren't going to focus on AMD versus Intel, since we've already looked at that aspect of battery life on these laptops. However, there's no getting away from the fact that the Intel platform offers substantially more battery life. Over 30% more time for each battery test means we only get three or four runs per day compared to four to six runs. (Note that it takes another 90 minutes or so between tests to recharge the battery, and we're not always around to immediately plug the laptops in at the completion of a test.) That means it takes the NV58 anywhere from 4.5 to 6 hours per test compared to 3.5 to 5 hours for the NV52 - and we do need to sleep at some point.

The average increase in battery life over all of the tests we performed so far is 33%, and that's taking into account the fact that Ubuntu closes the gap quite a bit between the two platforms. Throw out that Ubuntu result (only 13% in Intel's favor) and the average battery life lead increases to 37%. Why should we throw out Ubuntu? If you took the time to read this article, you already know that Ubuntu is consistently the worst battery life of the tested operating systems. As much as people like to complain about Windows, manufactures have worked a lot more on optimizing battery life performance for Microsoft's OSes. Then again, as we repeatedly mention in laptop reviews, Apple's OS X is in a league of its own when it comes to battery life. Not surprisingly, having full control over your operating system and hardware can give you a real advantage when it comes to laptop mobility.

The final topic to address is OS performance. Again, we have to pretty much throw Ubuntu out of the running. These are by no means high-performance laptops, but surfing the Internet using Firefox on Ubuntu makes you think you're running an Intel Atom netbook instead of an entry-level notebook. By no means are we discounting Linux in general, and it's still very difficult to beat the price (free); however, we think the vast majority of users will be more than happy to pay the cost for a Windows operating system. Looking at performance on the Windows OSes, once again there are some interesting trends to note. In PCMark05, Windows XP consistently scores higher in every individual test than Vista and Win7; the exception to this statement is the 2D Transparency test, which makes it look like Windows XP is old and outdated. Generally speaking, Windows XP just feels a little snappier than Vista on these laptops, probably due in part to the fact that it has a smaller memory footprint. On the other hand, Windows 7 is the clear victor in general system performance. We would love to have PCMark Vantage results from Windows XP, but unfortunately that's not going to happen. As it stands, Windows 7 outperformed Windows Vista by 15-20% in PCMark Vantage; the individual multitasking test results in PCMark05 also favor Windows 7 over Vista by an average of around 5%.

Without running a reasonable number of game benchmarks, we are not prepared to make any statements about the 3D graphics performance of any of the Windows operating systems. The various 3DMark tests show little to no difference on the NV52, but the NV58 shows differences of 3-19% in the earlier versions and a whopping 84% difference between Vista and Win7. Considering that these notebooks are anything but fast when it comes to gaming performance - IGPs still don't perform very well compared to discrete solutions - and the variations we see may simply come down to driver optimizations. We will leave any firm conclusions about differences in overall Windows performance among the various OSes to the desktop people for the time being. As a laptop OS, we would definitely take Win7 over Vista, but despite UI improvements we still find Windows XP to be more than adequate for most users. Secure? No, but still adequate if you know what you're doing. :-)

At this point, you're probably wanting more information, and admittedly we've only scratched the surface. How do other browsers fare on other operating systems? What about a better Linux distro than Ubuntu? What happens if we use FlashBlock - or a similar add-on - with these other browsers? Can we improve battery life by using a different media player or codec? What about Mac OS X, including differences between Snow Leopard and Leopard - and Tiger, Panther, and maybe even Jaguar if we want to go nuts? Give us time, because if there's one thing we know for sure it's that conducting battery life tests can take a while to complete.

To Be Continued….

Internet Battery Life, Round 2
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  • ascl - Tuesday, September 22, 2009 - link

    I was reading this thinking that it was an unusually bad review from anand.... then I reached the conclusion 2 + 3 and my complaint was answered! Using randomised web testing is terrible if you want repeatable results. Use an internal server with a fixed set of pages (and ads).

    Kudos!
  • vailr - Tuesday, September 22, 2009 - link

    Maybe compare battery life on a MacBook Pro running OSX Snow leopard vs. Windows 7 64-bit/Win XP 32-bit (in Boot Camp) vs. Ubuntu(?). Using VLC Media Player sequenced to play a series of several DIVX movies, for finding the running time under each OS.
  • gstrickler - Saturday, September 26, 2009 - link

    Anand has already done that with a MBP and OS X vs XP (and maybe Vista). Anyway, it would be good to see it repeated with Win7 in a couple months when they've had time to produce some reasonably power efficient Win7 drivers.

    In any case, a MBP is a great platform for the task, it will run all those OSs, the Nvidia chipset is well supported in all of them and it's pretty power efficient. Of course, with it's battery life, the tests might take a while.
  • Gamingphreek - Tuesday, September 22, 2009 - link

    Battery life in Linux, as it is a *nix based OS, needs configuring. You claimed that you couldn't find it, but honestly you need to find someone who has *nix experience then because it is honestly the most customizable of the OS's.

    Additionally, while you did a good job in following that website for advice, staying with the 'Safe' configuration is a grave error. All that merely does is use an old version of MESA (OpenGL driver) and an old Intel driver. I would honestly like to see you try out the 2.6.30.5 or the 2.6.31rc kernel along with the most up to date drivers from the XorgEdgers repository. Performance with those optimizations is honestly quite remarkable.

    Furthermore, I would suggest looking over lesswatts.org as well as running the PowerTOP application to see what is unnecessary. For instance, I have a script that disables my PCMCIA slot given that I do not use it. I also have my RJ11 based modem disabled. I have LaptopMode enable automatically when I unplug A/C power and disable when I plug in A/C power.

    Additionally, why did you turn off auto dimming?? That is a great feature that severely crippled the performance of Ubuntu yet again.

    As for Firefox/Shiretoko (Shiretoko is the codename for Firefox 3.5) that is a known issue with lazy programming. Downloading the Noscript or Adblock extension helps immensely with performance. Additionally Shiretoko/FF3.5 has a vastly improved engine when compared to FF3.0.

    Additionally, I don't believe you stated what file system you were using. EXT4 is vastly superior to EXT3 (While it isn't the default, among Linux users, it is rare for someone to choose EXT3 over EXT4) - especially when boot times are involved. Even still, it sounds like there was a broken script or something - Ubuntu 9.04 has the fastest startup/shutdown I have ever experienced.

    Honestly, Ubuntu seemed to draw the short end of the stick here. It takes time to configure the OS - I honestly expect more time to be given to configuring it like the other ones.
  • smitty3268 - Tuesday, September 22, 2009 - link

    While I agree with most of your points (you can definitely tweak linux down to the bare bones much more than something like XP to save power), I think it is perfectly acceptable to use a default distro that is commonly used. After all, he didn't go through the Windows registry, disabling services and hacking stuff there either.

    But in the end, let's face it. Firefox and Flash are horribly optimized for Linux. It's not exactly a surprise that they suck down more juice, given that they usually take about 5 times more CPU power than under windows.
  • Gamingphreek - Tuesday, September 22, 2009 - link

    Well that is the inherent difference between Linux and Windows.

    Thats like saying you aren't going to download and install drivers for Windows - Linux comes with all of them...

    And as a slight correction, Firefox isn't really the problem and Flash is horrible for any/everything BUT Windows.
  • JarredWalton - Tuesday, September 22, 2009 - link

    As stated, it wasn't intended to be a Linux review. This is a well-known Linux distro that is supposed to be "easy". I don't have the time nor inclination -- just like 99.9% of users -- to go into detailed steps for hacking and modding Linux. I fully understand that it is highly customizable, but so is a car if you're inclined to go that route. I drive a stock vehicle, and I use a stock OS.

    Downloading drivers isn't the same thing as downloading the latest kernels, creating your own conf files, and manually entering all sorts of settings that help enable/disable items to provide better power saving. My conclusion pretty much sums up my feelings: the out-of-box experience for Ubuntu is nothing special for a laptop, and if you are expecting it to "just work" you'll be disappointed.

    Given how much is available for tweaking in the Linux community, I'm frankly surprised that no one has apparently spent the time to make the default configuration far more sensible and easier to live with. I know how much fun it is to download and compile programs and edit configuration files, but I'd rather just have an easy interface that works without a ton of effort.

    I also fully recognize the inherent problems with Flash, so I put in numbers with Firefox and FlashBlock. It helps, but it doesn't help enough to equal the default Windows setup. There are other browser options of course, and if/when I get time I'll see about looking at some of them.
  • ekul - Tuesday, September 22, 2009 - link

    Ubuntu is a poor distro for battery life out of the box as many of its default settings belong on a desktop or even server system. With a bit of tweaking though it can easily get better battery life then windows. My netbook struggled to get 2 hours in XP, in ubuntu I can easily see 2:45 or more.

    As has been mentioned by at least one other commenter use the powertop tool (sudo apt-get install powertop && sudo powertop). This was written by intel to help find applications and drivers that were waking up the cpu too much and hurting battery life even if they didn't appear to be using very many system resources. The tool itself looks for many settings that are not optimal for battery life and offers to correct them for you so you don't have to go on a treasure hunt at all. I'd love to see what kind of improvement could be made with that tool alone.

    As an aside, a major oversight is idle battery life. All of your tests feature the OS as the minor player in the war against power consumption. In each test you have an application eating the majority of the resources. You should fully charge the battery and let the laptop idle at the desktop until it dies, testing each OS's ability to sleep long running processes and services. Perhaps leave an office suite, browser idling on a page and wifi connected to stop the runtime for taking too long.

    Finally using flash heavy websites heavily skews the results for both OS and browser battery life tests since you are sending both into battle missing limbs. It is well known flash is poorly written software at the best of times, causing well over 60% of all firefox and IE crashes. It has rudimentary 64 bit support, doesn't support hardware acceleration on anything but windows and if it isn't playing video (covered by the dvd test) is almost certainly on the page to serve an ad. No browser has any sort of control over flash (though chrome does its best to reign it in) so your browser tests amount to little more then a test of flash. Flash sucks even in windows but in linux it is truly awful (as is almost all closed source code for linux).
  • JarredWalton - Tuesday, September 22, 2009 - link

    The second batch of sites was hardly Flash-heavy. Yahoo and MSN have one Flash ad, YouTube has none, and the Facebook login page is just text and images.

    FWIW, I did run an "idle at desktop" test on Ubuntu on the NV52 and got a time of 204 minutes. That compares to 242 minutes under Vista, or a 18.6%. There are a LOT of other things I still need to look at, however -- including different power schemes, tweaked profiles, etc.

    If I'm going to try to improve the Linux results in every way possible, it's only fair to do the same for Windows.
  • ekul - Tuesday, September 22, 2009 - link

    Because the linux and windows philosophy is so different a different approach has to be taken to setting them up and running them. With windows initial setup is very simple and has vendor support for things like drivers. Over time problems begin to appear and cleanup/formatting becomes necessary. Most linux distros integrate all possible hardware support and target lowest common denominator hardware to ensure broad compatibility at the expensive of performance. Once they have been tweaked they will continue to run indefinitely at that level.

    With windows you have ease now for pain later. With linux you have pain now for ease later. This means running things like powertop and changing the init options to run in parallel would be the same as cleaning a registry in windows rather than something like disabling services in windows. I spent one afternoon tweaking my netbook and now it runs much smoother and faster then it ever did with windows plus the battery life is longer. Changing config options and customizing for your hardware is the reality with linux the same way random problems cropping over time is the reality with windows. If linux distros are to be punished for ease of setup issues then windows must be punished for altered performance 6 months from now. Linux is getting better however, and different distros ship with very different defaults. Ubuntu is really debian unstable repackaged for the server/desktop which means at its very heart it is a server distro. For future tests opensuse may be the best choice to represent laptop/desktop defaults.

    FWIW if you want to find the real options in linux for power management you should look in /sys/devices/system/cpu/cpu0/cpufreq/. The options in the gnome power management panel only really deal with monitors. But again 3 minutes with powertop and I'm certain you will see an improvement.

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