Spin down hard disk when idle - whats the point?

[CubeHacker]

I have that "Put the hard disk to sleep when possible" box checked under the energy saver tab, which is supposed to spin down the disk when the computer is idle to save power and to slow wear on the hard disk. However, i've noticed that when it spins down, it just spins right back up again within a minute or two! So all throughout the night, the hard disk is just constantly spinning down and up again, at intervals of 5 minutes or so. I don't see the point of this, and I believe its even more harmful than just letting the disk spin all night long. Obviously, OS X is reading/writing something when the computer is idle which is waking the drive up, but I don't have any apps open. It just seems useless to me to have this feature when it doesn't actually work like its supposed to. Does anyone else have this problem? Or perhaps a fix?

 

[tomf87]

Same here.... I just put the entire computer to sleep instead of just the hard disk.

And you're right, it is harder for a disk to spin up and down rather than keep it spinning. It's more work on the motor inside for it to start the spinning, rather than keep it spinning.

 

[blue&whiteman]

I don't even use that option. I find in certain areas of the os my performance went down by having it on. it would spin down even when I was activly using my comp and therefore have to spin back up to access a file for me. when it would spin back up to open a file it took at least 3-4 times longer than from an active up drive. don't use this option.

 

[mnkeybsness]

i use it because i have two hard drives. the main drive is almost always being accessed, while the second (music only) drive is not accessed all the time. this saves power consumption mostly, but can also help to keep the drive heads from getting trashed.

 

[big]

well, it works very very well with my external drives, I may not see them, or use them for another 6 hours, when I backup tonight, again, I might use them in the next hour, there's no telling. Though the PB drive keeps on going since I am always on it.

 

[janey]

i LOVE it. My lacie drive is loud and I hate unplugging it, so when it spins down after a minute or two, its all blisfully quiet...

 

[XnavxeMiyyep]

Because I have 2 hard drives, I don't use this option. Opening files is really irritating when the hard drive you want is asleep.

 

[blue&whiteman]

Because I have 2 hard drives, I don't use this option. Opening files is really irritating when the hard drive you want is asleep.

exact reason I don't use it.

 

[Doctor Q]

And you're right, it is harder for a disk to spin up and down rather than keep it spinning. It's more work on the motor inside for it to start the spinning, rather than keep it spinning.

There must be a break-even point. If you are going to the refrigerator to get a snack, you don't want to spin down the hard disk. If you are going to Florida for the winter, you certainly do. Has Apple addressed this issue directly? I'd like to know what they have to say about the ideal spin-down times for various types of Mac hardware.