How can SATA power management feature be controlled?

[Peter van Hooft]

> How can I control the automatic power management feature of my SATA disk
> drives?  Right now the heads are unloading so frequently that within
> one year I will have exceeded the rated number of load/unload cycles for
> the drives.  The drives are Western Digital model WD10EADS.  I tried
> using "hdparm -B 254" and "hdparm -B 0", but neither works:
>
>    # hdparm -B 254 /dev/sda
>
>    /dev/sda:
>    setting Advanced Power Management level to 0xfe (254)
>    HDIO_DRIVE_CMD failed: Input/output error
>    HDIO_DRIVE_CMD(identify) failed: Input/output error
>    # hdparm -B 0 /dev/sda
>
>    /dev/sda:
>    setting Advanced Power Management level to 0xfe (254)
>    HDIO_DRIVE_CMD failed: Input/output error
>    HDIO_DRIVE_CMD(identify) failed: Input/output error
>
> My efforts to find anything useful with 'sdparm' have been fruitless.
>

Hi,

I use both:
hdparm -q -S 0 /dev/sda
hdparm -q -B 255 /dev/sda
which seems to work.

peter