MacBooks And “Safe Sleep”

/ 5 May 2007

I’ve known that all the new macs have the ability to sleep in the “Safe Sleep” mode. This mode is where the contents of RAM and other memory are copied to a database file on the hard disk when the mac is visibly put to sleep so it can load it all back from that database when woken up again. This sleep mode is the default on these new macs and it’s clearly active on my dad’s MacBook. I’m not positive about that, but the signs I’ve seen when he puts his MacBook to sleep and wakes it up seem like that mode is the active sleep mode. I’ve noted that when he closes the lid of his MacBook the sleep light turns on but the screen doesn’t turn off for another few seconds. This suggests that the copying is taking place. Then, some of the time when he wakes his MacBook up it takes a few seconds for the screen to turn back on. This suggests that the restoring from that database file is taking place. Obviously these are just my assumptions based on what I know of the “Safe Sleep” mode and the intel macs, so until I have my own MacBook and can do deeper research on the topic I can’t be sure of these assumptions, but I can easily make an educated guess that the “Safe Sleep” mode is what’s taking place during these semi-long periods of (sleep??) time for his MacBook.