Why Does Windows Have Terrible Battery Life? 558
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.'"
Re:Multitasking support (Score:3, Informative)
Funny you should mention Symbian - my S^3 phones had the best battery life of any of my smartphones, regardless of platform, without having larger batteries than their iOS/Android/Windows Phone counterparts.
Comment removed (Score:2, Informative)
Stupid troll submission (Score:5, Informative)
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.
Re:The (linked) Aandtech article on battery life.. (Score:5, Informative)
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.
Re:Easy one... (Score:5, Informative)
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.
Re:Easy one... (Score:5, Informative)
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 [codinghorror.com], 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.
expanding... (Score:5, Informative)
(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.
Re:Easy one... (Score:5, Informative)
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.
Sony Vaio Pro (Windows) vs. 2013 Macbook Air (Score:5, Informative)
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.
Re: Apple power mgmt (Score:3, Informative)
This happens because you don't have the correct Intel thermal profile driver installed. There won't be any unknown devices in Device Manager, but you still need to install it or you will see the behaviour you are getting in Windows.
Intel allowed manufacturers using C2D processors to customize the thermal profile of the CPU based on what their hardware was capable of. That's how very thin and light laptops were able to use high end CPUs without overheating, but limiting the amount they can ramp up CPU speeds and voltages, particularly when both cores are loaded or the GPU is also active.
Apple must provide the correct drivers, tailored to their laptops. Presumably you can download them from somewhere.
Re:Reduce (Score:5, Informative)
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...
Re:Easy one... (Score:2, Informative)
Windows does a lot of things in the background, all the time.
Find me one operating system that doesn't do things in the background all the time.
My Dell Laptop (and ancient 9400 that refuses to die), gets WORSE battery life on Linux than it did on Windows XP that it came with.
Linux does stuff in the bacground too.
But its not just YOUR answer that was stupid, the question itself was stupid.
The processors between Android and and IOS and the Surface Pro are all different. Apples / Oranges.
The operating systems were not designed with energy efficiency in mind.
Android and Apple have focused on ARM processors for a reason. They are incredibly power efficient. That is the ARM's whole raison d'être.
Re:Easy one... (Score:3, Informative)
Microsoft is only organization who can answer that question. No amount of beating on it or guessing is going to provide the answer. There's no point in asking that question to anyone except the engineers building the software, that was my point.
Oh, come on, none of this is secret.
Every DLL loaded and running in a Windows machine has a purpose, and you can google it to find out what it is.
There is no magic here, and even though the code is not opensource, its fully known what just about every part
of windows is doing.
On the other hand, look at all the running and "sleeping" processes in your Android phone. Some, that are part of
Android itself you can actually figure out what they are by reading the code. Others are inserted by manufacturers and carriers,
and nobody knows what they do or who they serve.
Re:Easy one... (Score:2, Informative)
Your giving the same answer, so you get the same reply.
The purpose of every single DLL in the windows system is known, and documented. You don't get the source code, but this is not some deep mystery.
Re:Easy one... (Score:4, Informative)
Because it wasn't designed with power management in mind. Duh. The engineers who wrote some of the subsystems probably took shortcuts that they knew would suck up power (indefinite loops or some such) but were easy to implement. It is a desktop OS.
BSD, on the other hand, was built with embedded systems in mind.
No, it wasn't. If we go back to 3 and 4BSD, it was built with VAXes in mind; even if we only go back to {Free,Net}BSD (Open and DragonFly forked off from them), it was built with PeeCee's in mind.
And NeXTStEP/OS X were also originally designed for desktops.
Desktop Linux, I hear, is pretty rough on power too, but not as bad as Windows.
Linux was also originally built with PeeCee's in mind.
So Windows, OS X, Linux, and *BSD were all originally built with personal computers in mind; all the power-saving stuff largely came later, as 1) notebook computers became more popular, 2) some of those OSes were taken into lower-power embedded systems, and 3) some of those OSes were taken into smaller mobile computers.
Re:Easy one... (Score:4, Informative)
(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.