Force Spindown Mac HDD

taylorconor95

Does anyone know if there is a way to FORCE immediate spindown of HDD'd on a mac? I have two drives in my MBP and i only need one spinning... I have tried things like CHUD and Xupport, but they only allow you to set the time after which the disk spins down, it dosent let you force it to. Any ideas???

Sad Professor

Forcing it to spin down probably isn't a good idea. The system and other apps might be using it, Why do you want to do this?

taylorconor95

Battery

taylorconor95

OK I finally figured it out!

If I go into disk utility, right-click the PARTITION of the disk I want to spin down (not the volume) and select unmount, it unmounts, but it keeps spinning...

Now, go into terminal, and type:

diskutil eject <PARTITION-NAME>

This ejects the whole disk, spinning it down too.
Simply going into the disk utility application un-ejects(?) it, but you still have to re-mount it through disk utility.

Sad Professor

Yeah, but you can't unmount the startup disk, so doing this won't make any difference to battery life.

taylorconor95

This is not the startup disk, its another HD I have in my Mac as a replacement for the optical drive

Sad Professor

Oh, well in that case just ejecting the disk in Disk Utility or in the Finder should do the trick.

taylorconor95

nah that only unmounts the disk. Apparently there is a difference (I did not know this already in fairness!):
http://www.thelinuxdaily.com/2010/01/difference-between-eject-and-umount/

Sad Professor

Once all the partitions are unmounted it should spin down anyway.

taylorconor95

Well mine didn't, even when I manually set the spin down time to 1minute (minimum) using spindownHD. It was only when i do this in terminal that it works immediately every time