It's a known issue and will be fixed..For now, I can guarantee that disabling hibernation will fix you up for now. Your Mac will still sleep, as normal, and you will do no damage by running the terminal commands posted in the link.
I have applied the fix to 3 Mac's now and it's cured all of them.
Just to make it easy to use the terminal commands, here they are again:
Open a Terminal shell (in the /Applications/Utilities folder)
pmset -g
will list all the current power settings/device settings.
1. set hibernate mode to 0
sudo pmset -a hibernatemode 0
hibernationmode 0 is normal sleep, data kept in ram, nothing written to disk
2. delete the unnecessary sleep file to regain disk space equal to memory (saves the same amount of disk space as your RAM, eg. 8 GBs, valuable on an SSD), since hibernate is disabled
You can use the Go to folder menu to delete the file, found in the /var/vm/ folder, and named sleepimage. Reboot and simply delete that file,. Or use this:
sudo rm /var/vm/sleepimage or sudo rm /private/var/vm/sleepimage
The sleep image file is actually in /Private/var/vm/ but /var/vm/ is a symbolic link to that location.
Optional: Create a blanked zero-byte file so the OS cannot rewrite the file:
sudo touch /private/var/vm/sleepimage
Make the file immutable:
sudo chflags uchg /private/var/vm/sleepimage
3. If pmset -g shows: autopoweroff 1,
disable this automatic hibernation mode (happens even if hibernation mode is set to 0 on the new Mac mini 2012 and iMac)
sudo pmset -a autopoweroff 0
4. set the safe sleep timer (standbydelay) to 20 hours, default is 4200
sudo pmset -a standbydelay 72000
5. sudo pmset -a standby 0
While researching this, I noticed that bit 3 of hibernatemode encourages the dynamic pager to page out inactive pages prior to hibernation. So this appears to be why I have swap used after sleeping (even though my hibernatemode is 0, so bit 3 is off). I disabled this new, possibly buggy behavior by switching off standby: sudo pmset -a standby 0
