Is it possible to configure OSX Mountain Lion to go from suspand-toRAM to suspend-to-disk after certain amount of minutes?

The default sleep mode seems to be suspend-to-RAM until the battery is almost empty. This makes it troublesome for traveling with the laptop as the battery is guaranteed to go to empty after closing the lid and putting your computer to the bag for a day or two.


According to the pmset man page,

hibernatemode = 3 (binary 0011) by default on supported portables. The system will store a copy of memory to persistent storage (the disk), and will power memory during sleep. The system will wake from memory, unless a power loss forces it to restore from disk image.

But then also

standby causes kernel power management to automatically hibernate a machine after it has slept for a specified time period. This saves power while asleep. This setting defaults to ON for supported hardware. The setting standby will be visible in pmset -g if the feature is supported on this machine.

standby only works if hibernation is turned on to hibernatemode 3 or 25.

(which it is by default on supported portables)

standbydelay specifies the delay, in seconds, before writing the hibernation image to disk and powering off memory for Standby.

On my machine, with settings that I believe are default, when I type pmset -g |grep standbydelay I get the result of 4200, meaning that after 70 minutes of sleep, the machine cuts power to the memory and restores from the memory image saved to the hard drive.

If your settings do not look like this, the pmset command just might be your new friend.

  • What kind of machine do you have and does pmset -g | grep standby return 0 or 1? On my 2011 MacBook Pro running 10.8.1, I have 0 with a delay of 4200 (I haven't changed these). I could be wrong, but I believe this feature is disabled by default for non-SSD Macs (since they take so much longer to wake from disk). – gabedwrds Sep 10 '12 at 9:00
  • I have a MacBook Air, and on my machine, it returns 1. – Daniel Sep 10 '12 at 14:20

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .