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Why Does Windows Have Terrible Battery Life?
An anonymous reader writes "Jeff Atwood at Coding Horror is trying to figure out why the battery life for devices running Windows is so much worse than similar (or identical) devices running other operating systems. For example, the Surface Pro 2 made great strides over the original Surface Pro, increasing web-browsing battery life by 42%, but it still lags far behind Android and iOS tablets. The deficit doesn't get any better when Windows is run on Apple hardware. Atwood says, 'Microsoft positions Windows 8 as an operating system that's great for tablets, which are designed for casual web browsing and light app use – but how can that possibly be true when Windows idle power management is so much worse than the competition's desktop operating system in OS X – much less their tablet and phone operating system, iOS?' Anand Lal Shimpi is perplexed, too. Atwood is now reaching out to the community for answers: 'None of the PC vendors he spoke to could justify it, or produce a Windows box that managed similar battery life to OS X. And that battery life gap is worse today – even when using Microsoft's own hardware, designed in Microsoft's labs, running Microsoft's latest operating system released this week. Microsoft can no longer hand wave this vast difference away based on vague references to "poorly optimized third party drivers." ... I just wish somebody could explain to me and Anand why Windows is so awful at managing idle power.'"
Only on Apple hardware, which requires Apple drivers for power management, and surprise surprise, Apple sucks at Windows drivers (and always has). In one particular, the Windows power management drivers for my friend's MBP don't suppose variable fan speed control. It always runs full speed. No shit, that's going to waste battery life... On the flip side of the coin, though, Hackintoshes get worse battery life than Windows on the same hardware. This entire "article" is stupid; anybody who isn't blinded by fanboyism and has used the systems in question could tell you that.
Surface Pro [2] has worse battery life than an iPad or Android tablet for a simple and bloody obvious reason: Core i5 CPU. Not some power-sipping little ARM chip with passive cooling, but full laptop-grade 64-bit processor. Even completely leaving aside the obvious (to anybody who is not an idiot, which apparently excludes the submitter) differences between a desktop OS (Win8.x) and a mobile one (Android or iOS), there are very obvious reasons for the battery life difference.
There's no place I could be, since I've found Serenity...
Errm, what article are you reading? Because the one I see shows the Haswell-powered 13" MBA getting ~14 hours of battery life to the Surface Pro 2's ~7 hours of battery life. Sure, the 13" MBA has a bigger battery, but the 11" MBA has a smaller battery and still gets ~11 hours.
Your arguments about the Surface Pro 2 not really being microsoft hardware are not really meaningful, you could say the same about Apple's notebooks. They don't make the CPU, or the GPU, or the SSD controller, or the screen, or the display controller, etc.
I don't think age has much to do with it. Linux is older than Windows. Remember the current incarnation of Windows is derived from NT, a completely separate set of code from regular Windows originally released in 1993, with Linux originally being released in 1991. Linux wasn't even intended to be a production OS either, it was originally written as a i386 learning experiment.
Yet Android, which runs on Linux, manages to do much better in battery life.
Careful with names containing L slashdot.org/~AiphaWolf_HK slashdot.org/~AlphaWoif_HK slashdot.org/~AiphaWoif_HK
It really is a simple question.
I just wish somebody could explain to me and Anand why Windows is so awful at managing idle power.
OK, Jeff and Anand, listen up: it's because Windows is doing things in the background.
What is it doing? Ask the engineers that built it. But there's no reason to ask stupid vague questions like that when the general answer is so obvious. Windows does a lot of things in the background, all the time. It sounds like that carried over to the mobile version. If you want to know exactly what it's doing in the background (for academic purposes, I assume, since that knowledge isn't very useful) then feel free to ask the people who designed and wrote the software instead of the general public.
The benchmark used by the Anand and Jeff is OS X, which is doing a lot better batterywise than Windows 8. Neither of these are mobile, and both of these have a lot of background processes.
(1) there is so much cruft under the surface in Windows (fake DOS calls, umpteen levels of virtualism, etc) that the machine expends a ton of cycles doing what is NOP in newer systems not supporting 1980 calls.
(2) optimization isn't pretty and doesn't sell, so Microsoft is not cleaning house.
if this is supposed to be a new economy, how come they still want my old fashioned money?
So, linux and OSX aren't doing anything in the background too?
Sure they do things in the background, they just do it more efficiently than Windows.
Only to idiots, are orders laws.
-- Henning von Tresckow
Moreover, the Sony Vaio Pro has a higher-resolution screen than the MBA, which puts the Vaio at a disadvantage (because it drains the battery a little faster). So with highly-optimized Windows drivers, the battery life looks the same or even better for Windows.
The comparison to ARM is just stupid. Obviously battery life is better on ARM, at the cost of much lower performance. That's true for Windows and OS X both.
Pretty sure Windows generally gets (sometimes substantially) better battery life than Linux.
Rubbish. The netbook I'm typing this on right now dual-boots Ubuntu (full Unity bloat version) and Windows 7 Starter. It gets (or used to get a year or so ago, when the battery was a little newer) 6.5 hours under Ubuntu, more like 4.5 under Windows.
Windows just isn't built to be light. It tries to do A LOT in the background to "improver your experience". Some of which might even work. But a lot of it will turn out to have been wasted effort ("Wow, you've indexed all the files in my Program Files folder, well done! If only I had any reason to access a single one of those files today..."). And in the meantime, you've managed to consume a full third of my battery...
(1) For the same reason that IBM inserted a 3-second delay in their mainframe's response to user input. Make it instant and people will complain the moment it is not. Make it a 3+ second delay and people get used to waiting.
Been working on IBM mainframes for 30 years and I've never heard of this. Sounds like BS to me. We mostly get (and have got for all of those 30 years) sub-second end-to-end response for 95%+ of production CICS transactions, unless the entire LPAR is running short of cpu capacity.