Re: Does Linux support powering down SATA drives?

Marc Perkel
2005-11-19T21:20:09Z

Alan Cox wrote:

>On Sad, 2005-11-19 at 19:00 +0000, Alistair John Strachan wrote:
>
>
>>>SATA not yet, USB you could however.
>>>
>>>
>>Or PATA, of course. I switch off two of my HDs 4 minutes after last use with
>>the commands:
>>
>>hdparm -S 48 /dev/hde
>>hdparm -S 48 /dev/hdg
>>
>>Isn't there a passthru patch in the works to let commands, such as the one
>>required for suspend, through to a SATA device?
>>
>>
>
>The latest kernels support command passthrough for SMART and the like
>but hdparm -S does not "switch off" anything. It may spin a drive down
>but the power consumption of 23 hours a day of "spun down" is
>significant, probably more than the hour it is powered up.
>
>Same as the problem with many household devices in standby that actually
>end up using as lot of power in their many "turned off" hours
>
>

I didn't actually mean totally power off. Spin down would be fine with
me. Just seems like a waste to run a drive for 24 hours that is used
only for 10 minutes. That drive is there so if the main drive blows I
can run down to the datacenter and move one cable and be back up again.

You know what's interesting is that I read somewhere that computers use
as much power as 4 hoover dams can generate. And since a lit of these
computer are running Linux just a few lines of code can create enough
energy savings to perhaps power a small city. Kind of amazing when you
think about it.

SATA isn't really "new" any more. I personally consider IDE to be
obsolete. Seems to me that Linux should fully support SATA to the same
level as IDE drives. And I'm saying that as someone who doesn't have to
actually code it. But I will leave messages of praise and thanks in this
mailing list if you all catch up.