Message-ID: <437FCA07.40600@superbug.co.uk>
Date: Sun, 20 Nov 2005 00:57:43 +0000
From: James Courtier-Dutton <James@superbug.co.uk>
User-Agent: Mozilla Thunderbird 1.0.7 (X11/20050923)
MIME-Version: 1.0
To: Marc Perkel <marc@perkel.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: Does Linux support powering down SATA drives?
References: <437F63C1.6010507@perkel.com>
In-Reply-To: <437F63C1.6010507@perkel.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1361
Lines: 29

Marc Perkel wrote:
> Trying to save power consumption. I have a backup drive that is used 
> only once a day to back up the main drive. So - why should I run it more 
> that 10 minutes a day? What I'd like to do is keep it in an off state 
> and then at night power it on, mount it up, do the backup, unmount it, 
> and shut it down. Can I do that?
> 

Support is being added soon, I think the latest 2.6.15-rc1 supports 
passthru. I had to install an extra patch due to a bug where it used the 
same IDE device irrespective of one asking for /dev/sda or /dev/sdb
I think the fix will be in rc2.

hdparm -S60 works fine for me. It spins down, and therefore stay nices a 
cool.
hdparm -y should work, and is like an immeadiate -S
hdparm -Y is kind of dangerous at the moment. It powers down the drive, 
but will not come back unless the entire IDE bus goes through a reset. 
The feature to support that is called hotplug, but that is not 
implemented yet for SATA. So, basically, if you do hdparm -Y, you won't 
be able to wake it up again at the moment. At least hdparm -S60 is a 
start towards what you want.

James
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/