The hard drive is not to be used as a NAS

I have the hard drive running on my Raspberry Pi, where it is used by XBMC as media storage and have set up an access in the Samba service. If the hard disk is running and you regularly work with it, all is well. But as already mentioned elsewhere, the hard drive goes quickly into sleep mode. Then the number of hits already take some time, because the hard disk must be run only once.
Then usually all folders are not directly available and have to be loaded on a second or two away. In this case, the hard disk is unusable.
As soon as I have time, another hard disk will take the place and this hard drive is used in the drawer as a backup. That seems to be probably even more benefits.