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Re: waking up an ata harddrive from idle/suspend mode without timeouts

From: Okan Demirmen (okandemirmen.com)
Date: Mon Aug 02 2004 - 16:12:53 CDT

On Mon 2004.08.02 at 17:06 +0200, Jochen Eisinger wrote:
> Hi,
>
> I want to spin down my (laptop) harddrive if I don't need it for some
> time. I can achieve this for example using
>
> atactl /dev/wd0c apmset 63
>
> This works fine, the hd spins down after some time. The next time
> something tries to access the hd thou I get timeouts (as predicted by
> atactl(8)) which isn't really too grave, since the wd driver can recover
> from this and just tries the request again.
>
> I wonder however why the ata driver didn't remember the apm level was
> set to something <= 126 and checks whether the device is suspended
> before accessing it. This would mean a performance loss, but hey, apmctl
> <=126 isn't meant for performance tuning, but to reduce power
> consumption and noise.
>
> Is there some way to achieve this behaviour (i.e. avoid the timeouts, or
> have the ata driver wake up the drive before using it)?
 
i use atactl /dev/wd0c setstandby <sec> with success. maybe that might
work better for you.

--
Okan Demirmen <okandemirmen.com>
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