Why does my MacBook Pro take so long to go to sleep?

Solution 1:

I recommend a nifty little utility called SmartSleep that allows you to control when the saving of your RAM contents to disk for the Safe Sleep / Hibernate feature Mac OS X has.

Alternatively you can disable Safe Sleep altogether by running: sudo pmset -a hibernatemode 0. To change it back to the defaults, change the value to 3.

0 - Old style - just goes to sleep.
1 - Only Hibernate
3 - Default - goes to sleep but writes RAM contents to disk just in case.
5 - Only Hibernate mode but if you use secure virtual memory.
7 - The Default but if you use secure virtual memory.

Solution 2:

Use the command pmset -g log to find out what is delaying the sleep command. Look for "applicationresponse.slowresponse" and "applicationresponse.timedout" entries.

Solution 3:

Another use for the pmset utility (which, like most Apple utilities, is documented: do "man pmset" in Terminal) is to tell the system to sleep when you hit the power button. In Terminal, do

sudo pmset powerbutton 1

and thereafter when you hit the power button a menu comes up with choices Restart, Sleep, Cancel, and Shut Down. I always sleep my MacBook Pro this way in order to be sure it has really gone dormant.

On the other end of the sleep cycle, I don't want the machine waking up while traveling if it gets jostled enough to shake the lid open (even briefly). The Terminal command to estabish this is

sudo pmset -a lidwake 0

For both commands, you will have to authenticate as an administrator.