Wikipedia:Reference desk/Archives/Computing/2017 November 16

= November 16 =

why did windows restart?
Hi, I just seem to have had a windows reboot, and don't know what caused it. There would appear to have been an update, acc to the update history. But I can't be sure because there's no timestamp on the update, just a date. Does anyone know where I can find a log file of restarts?? Or some other thing that will tell me exactly why my computer restarted? Cheers, IBE (talk) 01:37, 16 November 2017 (UTC)
 * That will depend on which Windows version you are running.  Here's a link I found for Windows 10:   RudolfRed (talk) 01:52, 16 November 2017 (UTC)
 * Thanks, I meant to say, Windows 10, sorry there. Will check link in due course, though currently I'm occupied, just quickly saving anyone else the hassle of not knowing which version. IBE (talk) 03:28, 16 November 2017 (UTC)

Windows 7 key
If you find the Windows 7 key using Belarc Advisor, how can you tell whether it's your key or the manufacturer's key? And does it actually matter, if you're reinstalling Windows from a backup DVD you made yourself onto a new, blank hard drive? 2601:646:8E01:7E0B:0:0:0:EA04 (talk) 02:15, 16 November 2017 (UTC)

App
I possess more than 83 app on my phone, What is the best solution: 1) Should I keep all my android apps on? 2) Should I only keep useful apps on? 3) Should I use apps when necessity arrives than "Force stop" them? 123.108.244.151 (talk) 10:08, 16 November 2017 (UTC)
 * Apps running in the background use up memory and slightly increase battery consumption (see below). Get rid of the ones that you never use, and force stop ( see below ) the others when you will not need them for a while.    D b f i r s   15:39, 16 November 2017 (UTC)
 * This is a myth. (probably spread by people with more familiarity with desktop OSes.)
 * On Android and iOS, with only a few exceptions, only the currently focused app is "running" in any meaningful way.
 * It's true that they're "using" memory, but the way memory management works on those devices makes that a good thing. The OS is empowered to kill any backgrounded app at any time if it needs the memory. So the only side-effect of leaving an app in memory is that if you switch back to it (before the OS decides to re-use that memory) it will load faster.
 * (This is very different than the memory management on a desktop. On a desktop, it's bad if an unused app is using RAM, because the OS isn't allowed to kill it.)
 * It's true that there are "services" that run in the background constantly. (If you install an email app, for example, it will have both an app which acts as I've just described, and a service which will run in the background and check your email regularly.) In most cases, force-stopping a service will just waste your battery because the OS will re-start it automatically moments later, and the start-up procedure will usually be more intensive than whatever it was doing just sitting there. This effect can be especially bad if you install one of those apps that automatically kills services. Those can drain your battery real fast because your phone will spend a lot of resources repeatedly restarting and killing the same services.
 * If there are services that are draining your battery you should uninstall those services. Force Stopping them when you're not using them will usually make things worse. ApLundell (talk) 21:42, 16 November 2017 (UTC)
 * I withdraw the "force stop" suggestion. According to the linked article, stopping "Background App Refresh" works better.    D b f i r s   22:01, 16 November 2017 (UTC)


 *  D b f i r s  : i read through the articles, couldn't find the "Background App Refresh" option, could you please guide me where it is? 123.108.244.135 (talk) 15:42, 19 November 2017 (UTC)
 * It was this article, and it refers to iOS rather than android, so the settings will be different on your phone.   D b f i r s   22:05, 19 November 2017 (UTC)
 * ApLundell, this might hold for newer Android versions, but at least on older Androids there are apps that drain power while in the background, e.g. some video players. 93.139.55.105 (talk) 19:35, 19 November 2017 (UTC)
 * The OS is empowered to kill any backgrounded app at any time if it needs the memory. This is also the case on modern desktop OSes, at least with default settings. This is called memory overcommitment. If physical memory becomes exhausted, the OS will kill processes as necessary; on Linux, this is done by the OOM killer. Android, of course, uses the Linux kernel, but heavily modified, so I don't know if it works exactly the same. Ignoring swapping, the one downside of having memory occupied is that it's unavailable for OS caching, which can speed up things, especially on systems with hard drives. The important distinction, rather, appears to be that apps "in the background" on Android and iOS are suspended, meaning they don't get CPU time. By contrast, on "regular" Windows/Unix, "backgrounding" is just something that applies to the windowing system. It doesn't mean anything for the process's status (running, sleeping, waiting, etc.). At least that's the case if I'm understanding things correctly. I'm not that familiar with Android/iOS programming. --47.157.122.192 (talk) 07:25, 21 November 2017 (UTC)

Battery life of a Smart phone
Recomendation desired to keep it extremely healthy. What are your experiences and what do you suggest? 123.108.244.151 (talk) 10:08, 16 November 2017 (UTC)
 * Charge the phone to 55%, turn it off, put it in the fridge and leave it there for 2 years. After 2 years, take it out and leave it out for a few days. Then plug it in and if the charge status is under 35%, charge it to 55% again then turn it back off, back in the fridge and repeat every 2 years. Nil Einne (talk) 15:26, 16 November 2017 (UTC)
 * That is, of course, the extreme example of how to prolong the battery life. Most people will wish to use the phone occasionally, and not keep it in the fridge, so a compromise would be to turn off all services and applications that you are not actually using (Wi-Fi, GPS, updates) and close down applications as soon as you no longer need them.  Keep the phone as cool as possible.  (Others will add other suggestions)    D b f i r s   15:36, 16 November 2017 (UTC)
 * Turning off features you're not using is a good idea.
 * "Closing down" applications after use has no positive effect, and sometimes makes the problem worse, as I've described above. ApLundell (talk) 21:44, 16 November 2017 (UTC)
 * Good points, though you are assuming that the applications stay dormant when not being actively used. Wi-Fi, GPS, and updates still drain the battery.   D b f i r s   21:48, 16 November 2017 (UTC)
 * In general, just closing the part of the app you can see will not fix that. ("updates" generally come from services connected to apps, not the apps themselves.) But you're right that there are exceptions. Anything that lives in your status area like an MP3 player or a navigation app, will continue to consume resources even when it's not he active app. ApLundell (talk) 22:05, 16 November 2017 (UTC)