When once again connected to a power source and turned on, you'll find the computer in the state you left it. The MacBook's battery is completely drained while the computer is asleep, and the computer shuts down.There are two situations where a Mac enters safe sleep: This way your work is saved if, for some reason, the Mac completely runs out of power. In other words, before macOS turns off all power to the system’s RAM, it makes an image of the system's current state, writes it to disk, and uses the sleepimage file that it creates to restore the system to the same state that the user left it in. With safe sleep on, when the Mac ‘falls asleep’ the contents of its main memory – open apps, desktop settings, work in progress, etc. This feature is similar to what is known as ‘hibernation mode’ in other operating systems. Clean 500MB of Junk for Free What Is Sleepimage?Įver since it was introduced by MacBook models in late 2005, Apple has used a neat feature called safe sleep.
