Re: Disk spin down issue on shut down/suspend to disk

From: Robert Hancock
Date: Mon Aug 06 2007 - 19:32:02 EST


Tejun Heo wrote:
Michael Sedkowski wrote:
Hmmm... If the problem only shows up on nx6325, it might be that ACPI is
pulling unnecessary stunt. Please apply the attached patch and report
when the disk spins down and up.
Disk spins down on "Pre-shutdown prepare" and then goes up and down on
"Power down".

Oh... crap, so acpi wants to sync cache on shutdown. I wonder whether
it spins down the disk correctly. Does emergency unload count increase
after each power down? Also, please post the result of 'dmidecode'.

I know that my Compaq X1000-series laptop does do some kind of ACPI games with the disk on ACPI power off (I assume it is putting the disk in standby before power-off at least). It also does this if you boot into DOS, GRUB, etc. and then hit the power button. Could be if the disk is dumb enough to spin up for sync cache and standby when there is nothing to flush, and the kernel does its own standby, this could cause an extra spinup/down..

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@xxxxxxxxxxxxx
Home Page: http://www.roberthancock.com/

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