ATAidle sets the idle timer on ATA hard drives, so they spin down when the period of inactivity has expired. To use it, you must be running FreeBSD with ATAng, so basically FreeBSD 5.1 or newer - alternatively, you can also run it on Linux - it's been tested with kernel 2.6.1, but should work with any recent kernel. Also, it is limited to detecting the first 8 ATA channels.
Usage: atacontrol [-h] [-l] [-s] [-i] [-I idle_mins] [-S standby_mins]
[-A acoustic_level] [-P apm_level] channel device
where
-h shows usage information -l lists installed devices -I sets the idle level spindown timer -i sets the drive into idle mode immediately -S sets the standby level spindown timer -s sets the drive into standby mode immediately -A sets the acoustic level, value between 128 and 254 -P sets the power management level, value between 1 and 254
channel the channel of ata controller
device the device of the ata controller (0 or 1)
You can find the correct channel and device by listing the installed devices with 'ataidle -l channel device'
Supplying channel and device numbers without any parameters will display information about the specified device.
Notes on AutoAcoustic (AAC) and APM support
Use of this feature is experimental, and may crash your computer - although it is believed to be stable, it is modifying hard disk behaviour as data is being read or written, so any fault in the drive could have disastrous consequenses for your data.
Meaning of various AutoAcoustic values:
0 Acoustic management disabled 1 Minimum acoustic output 2-126 Intermediate acoustic output levels 127 Maximum performance, maximum acoustic output
Meaning of various APM values:
1 Minimum power usage with Standby (spindown) 2-127 Intermediate power usage with Standby 128 Minimum power usage without Standby (no spindown) 129-253 Intermediate power usage without Standby 254 Maximum performance, maximum power usage
Some values may not be supported, in this case you will see an error message 'Set APM failed: Inappropriate ioctl for device'.