Understanding “Battery Life” in Mobile Devices

A tweetstorm occurred today between Paul Thurrott and Mary-Jo Foley about The Verge’s report of Battery Life of the new Dell XPS 13. It was half of 11hrs quoted by Dell according to The Verge, and of course Mary-Jo was disappointed. What followed was a storm of comments with everyone saying their piece about the subject. But you can’t help but realize the topic of Battery Life is so esoteric, even in this current age in which every battery units of laptops comes with chips in them with which we can accurately measure how much juice is available, and expectant lifetime of such battery.

The question is “What is Battery Life”? Answer is no two person, given the same device, will be able to answer you with definitive scientific accuracy what the battery life of their device is. This is because it varies from person to person with all things being equal. Battery Life is a reflection of your personality; how you use the device.

Therefore I need to pen a few conditions that affect battery life of a product for clarity.

When a reviewer receives a test unit, they are mostly not tested under the typical condition that a user will use such a device. A reviewer want to get his story out as soon as possible, therefore subjects such a device to certain standard test procedure, and exactly these test procedures could be detrimental to performance of such a product at the time. Like running a video-playback loop back to back with the screen adjusted to a certain brightness level. This is not the way a typical user uses the same device, therefore a perceived Battery Life for an End-User will be different from the reviewer.

Carmen Crincolli said it right in the tweetstorm, there should be no Battery Life Test without the mention of the Methodology used in measuring the test. For example, what are the running processes on the device during the test? What is the average CPU cycle of such processes. These are the things that affects battery life. If you’re running a video-loop test, but Chrome is opened in the background with 20-tabs open, you will not get much battery life.

So for me, these are this salient points that should be touched when measuring battery life performance:

  1. New Device State: Not many are aware of this, but when you’ve just install a vanilla OS, there are certain configuration and maintenance activities going on in the device that will impact performance.
    1. Indexing: This depends on how extensive you document and Media Library is. In these days of OneDrive access to an OS, a vanilla device will spend a great deal of time indexing the whole machine; including syncing and indexing gigs of your OneDrive data. If you run perf test in this period, you will not get a true picture.
    2. Updates: Don’t we all know it, when you first install an OS (hello Windows), there is a lot of resource used in downloading and installing updates. Think of Disk trashing and high CPU cycles. All these affect battery life. In fact you can only be sure of a stable environment after the first two days of a vanilla install, sometimes even more.
  2. Correct Drivers: Another point of contention not always visible to common users. Mostly by the time you get a bleeding new product, time has elapsed between the time it went into production and the time you get it in your hand. Therefore, it is almost always a good practice to visit the site of the OEM to download the latest and greatest drivers for all components of your device. This have performance and ergo, battery life consequences.
  3. Running Processes: This is where everyone will differ as there are no two people running the same processes on their device at the same time. So the question is what are the running process at the time of the measurement? What impact are they having on the Environment? Carmen mentioned Google Chrome in the tweetstorm. Yes, Chrome is a serious resource hog because Google is knowingly doing some funky things to your device to make Chrome run faster than any other apps. Things like adjusting the Clock tick rate to run at highest rate which is bad for the battery in particular and the device in general. Chrome seems faster because it is gaming the system at the expense of battery life. All these have consequences on environment.

Therefore there is no point for any reviewer to mention Battery Life without being scientific about it. We need to know the condition under which you did the measurement. There is a simple tool that is delivered by Microsoft with it’s modern OS called PowerCfg.exe. There is a switch of this tool that will tell at any given moment what is eating up your battery life. The Reviewers can at least run this test in the background and publish the result so we have a comparative case.

Battery Life is and will remain a mirage. I will never depend on a Reviewer’s report who used such a device in a day or two and come out with a “Conclusive” report. I will rather go to User Forums where real people using the product are quoting their experience. That is my yardstick, it should be yours too.

Understanding Windows 10 TP Battery Performance on Mobile Devices

I’ll give you the poison pill straight away: Windows 10 cannot and will not be as Power-efficient compared to Windows 8! Not on an x86 device. On ARM, it’s another ball game. This is why MS is having issues with ARM devices and Desktop for Windows 10 generally.

See, the reason here is simple, since the rejection of Windows 8 platform by the masses who doesn’t understand the OS, Microsoft’s hand has been forced to abandon all the progress made on re-writing Windows from the ground up for a great mobile experience, and concentrate on the Keyboard & Mouse world to make Windows 10 acceptable to Desktop huggers and the Enterprise in general.

This means dumbing down the progress made in Windows 8 timeframe and bringing up Windows 7 UX to the next century. For me I don’t consider Windows 10 the next evolution of Windows 8, but an evolution of Windows 7 with a nod to Tablet/Mobile users with the Continuum technology in it. Windows 10 is Keyboard/Mouse first and Touch second.

Which brings me to the topic at hand. Because of Desktop and UX technology of Windows 10 that mimics Win7 UX, you get to keep lots of windows open. Each opened Window is an active resource in Win10, which means active drain on the battery.

Compare this to Windows 8 which is a single focus OS. The currently opened window in Win8 is the only window tasking the CPU, all other “invisible” windows are put on ice. Sleeping if you get what I mean. The only type of windows that tasks the system while not in focus are those that you allow to run in the background specifically. And guys, this is why you get the warning when you have too many background task Apps in Windows 8 and 10. Like the max number of Apps that can put messages on the Locked screen for example.

On a Desktop device that is continually powered, you will not notice this issue, but if you’re on any x86 mobile device with Desktop, you will have this problem if you do not activate the Tablet mode. The only way to avoid battery wastage then is to minimize every windows you’re not using while on a mobile device with tablet mode not activated. When windows are minimized, they are put to sleep like in Windows 8.

As you can in the title Picture above (click to see larger), I have taken my favorite TV app TrackSeries as an example. This modern app makes full use WPF with lots of eye-candy and animated thingymagic all over the place. As you can see above, even while it is out of focus, it is still draining the CPU at 13.5%. (Of course this is a snapshot, it varies continuously.)

Now take a look after the App was minimized:

The system puts the app to sleep after a few seconds. You will notice some apps that are still active even after they’re minimized while not been set as background apps. These are apps like twitter and mail clients that are making use of connected standby feature of Windows 8/10 that is designed to keep your info-stream up to date even when your app is iced.

So to save battery in Windows 10 x86 (i.e. screen >= 8″) devices, either activate Tablet mode (which essentially switches you to Win8 single-focus mode) or actively minimize all windows you’re not using.

Final note: Please realize this post only relates to Windows Store Apps or Modern Apps like Microsoft like to call them. Those of us puritans call them Metro Apps for nostalgia sake. I am not talking of old Win32 desktop Apps, which will continue to drain battery whether you have them minimized or not. (That is why we developed Metro Apps technology in the first place!). For example, IE11 you see here above is Win32 App.

So now you know. If the same device that was reaching 8 to 10hrs with Windows 8 is not reaching it anymore with Windows 10, you might want to watch how you’re using Windows 10 regarding windowing. For me, I always have the TaskMan icon next to the clock to keep an eye on my CPU=battery drain while I am in mobile mode.

Have you noticed this yourself, or do you disagree with me? Comment below and let’s have intelligent discussion about this.

How to Go Fullscreen in Command Prompt and Powershell

PowerShell Featured

Note: You must have at least Windows 10 for this to work.

You can use Windows Command Prompt (cmd.exe) and PowerShell (powershell.exe) in fullscreen mode. To enter fullscreen mode, follow the following steps.

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Windows 10 for Phones May Likely have External Keyboard Support

Earlier today, I spotted a news article by Newoin, which you can see here, that showed new leaked screenshots of Windows 10 for phones and small tablets. I noticed something very interesting on one of the screenshot. Continue reading

SoundRecorder now saves to Documents folder in Windows 10 JTP

The Sound Recorder App was one of the updated apps for Windows 10 January Technical Preview. The Sound Recorder App in Windows 8 was excellent, but it has a nasty design fault; you can’t get to the recordings unless you’re a geek that knows how to hack your device. The files then were always saved in the hidden AppData folder of user’s Profile. Since this folder and its subfolders are invisible to normal users, they don’t care about it’s content. Therefore it doesn’t get backed up except you’re using a backup program. For example users are used to dumping their MyDocument folder on a thumbdrive etc, but not the AppData folder. Therefore, when the system needs to be refreshed/re-installed, the data in AppData don’t normally survive the system reload. All your recordings gone thus. Now, this has been addressed in Build 9926 as you can see above. Sound Recorder now saves by default to your My Document folder under “Sound Recordings” sub-folder. This is joy as your recordings are now conspicuous and gets backed up or made redundant. That OneDrive you see in the screenshot is just me making MyDocument folder point to OneDrive. Continue reading

Demo: Chitchat with Cortana in Windows 10 JTP Build 9926

Here’s a demo showing how Cortana responds to fun queries. This video demonstrates mostly chitchat. I also tried to demonstrate the “Hay Cortana” feature, but, sadly, I had no luck. Anyway, enjoy!

Can’t see the video? Click here.

Microsoft is about to release Win10 FBL_Awesome Build 9931 [Update: Nope!]

 

[Update] It seems this is a false alarm folks. You can now stop pressing the Retry button. We’ve just been informed by @GabeAul this upgrade is meant for Microsoft internal. We may eventually get it, but for now, it’s no go.

Original Text

Earlier this evening there was a tweet from @GabeAul that a security update is released for Windows Insiders for Flash. Of course you when you see this you run to the WU to download the update. For me however there were plethora of updates available including one specifically for Win10 and one for my DisplayLink driver. It all went too fast I wasn’t able to take a screenshot. Continue reading

Network is back in Windows 10 JTP

A few weeks back we informed of a development in Windows 10 Build 9879 in which Microsoft changed the name of Network node in File Explorer to “Computers and Devices”. Well guess what, they’ve changed the name back to Network with January Technical Preview (Build 9926) as you can see in the image above. Continue reading

Windows 10 JTP Alarm App Blew Us Away

Via the watchful eyes of our good friend @WinObs came a simple tweet about the new Alarms App in Windows 10 JTP with the screenshot as above. Of course I became curious as I haven’t had the time to checkout the app. I was instantly blown away. It is the most complete Alarms App we’ve been asking for and top it all, it has World Time Zone built-in! Continue reading

Bringing back the Start Screen in Windows 10 JTP

Our favorite hero Bavo Luysterborg got into discussion of bringing back the Start Screen as you can see above. The point is whether this trick that worked for Build 9841 would work for 9926.
He went ahead and tried it himself as follows:

Bring back the pre-9926 start menu in 9924:
HKCUSoftwareMicrosoftWindowsCurrentVersionExplorerAdvancedEnableXamlStartMenu – DWORD 0

He then tweeted the following:
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New Windows 10 JTP App from Microsoft: Student Planner

Here is another gem from Windows 10 January Technical Preview for all of you Students out there to track your Study Schedules etc. It is a good place to start your day and make plans for your courses. You can enter Course, Assignments and Exams. You can link to Outlook Mail app, OneNote and your files on OneDrive. Continue reading

Microsoft Released Customer Support App with Windows 10 JTP

There is a new Support App in Windows 10 January Technical Preview to obtain support directly from Microsoft for Windows. This shows how serious Microsoft is about it’s business of converting Windows into a Service. There are lot of people that will be needing assistance understand this new Windows and understanding the new Service structure. Continue reading

Breaking: New OneNote Universal App is Live for Windows 10 JTP

I was using OneNote a moment ago and I had noticed my new Windows 10 January Technical Preview has finished all updates after install and wants to reboot. So I finished my work, saved everything that needed to be saved and I restarted the machine. Continue reading