Windows 8 and its power-saving touch

As more details continue to emerge about Microsoft's latest operating system, the power-saving capabilities of Windows 8 and how it interacts with applications is coming to the forefront.

The details had been summarized previously

Most of the details had been summarized previously by Microsoft while its Build developer conference in September, when the Windows 8 developer preview was unveiled. The basic idea is that background apps get suspended by the operating system to conserve battery life, which is especially useful for mobile-device users. Lead program managers at Microsoft, Sharif Farag and Ben Srour, expounded on that concept in a "building Windows 8" blog post Feb. 7.

Perhaps the most interesting tidbit explained in the post is that Windows 8, when released as a product, will let the user close an application via touch, keyboard or mouse. This point, seemingly trivial, likely will be a tremendous relief for those who tried the Windows 8 developer preview tablets in September, which required the user to go find the Task Manager and kill an application in order to close it.

Still, Farag and Srour make a strong case for not closing apps at all when using Windows 8. Apps that a user isn't directly using will get suspended by Windows 8, and during those suspended apps consume some system memory, they draw no power, so there is no battery drain from them "running."

Microsoft makes a few exceptions to this power-saving scheme for background apps that play music, print, receive instant messages or e-mail or VoIP (Voice over Internet Protocol) calls, synchronize or share content, download or upload files, or refresh "live tiles." If the apps running in the background are "Metro-style apps," they can perform those operations concurrently with an active app. Windows 8 comes with an application programming interface that lets developers enable background processing for Metro-style apps, if needed. Another exception is antimalware applications, which may need to initiate a scan based on activity on the system.

Metro-style apps are written to take advantage of the new Windows Runtime environment introduced with the Windows 8 developer preview. They differ from so-called "desktop apps," or the classic menu-driven x86-based applications that are seen running on current Windows systems.