Load Cycle Count

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Changed:

< Read about the problem here: [[http://ubuntudemon.wordpress.com/2007/10/30/ubuntu-is-not-causing-aggressive-power-management/]].

to

> Read about the problem here: [[http://ata.wiki.kernel.org/index.php/Known_issues]] and [[http://ubuntudemon.wordpress.com/2007/10/30/ubuntu-is-not-causing-aggressive-power-management/]].


Read about the problem here: http://ata.wiki.kernel.org/index.php/Known_issues and http://ubuntudemon.wordpress.com/2007/10/30/ubuntu-is-not-causing-aggressive-power-management/.

Check the count with:

smartctl -a /dev/hda|grep '^193'

Find out how many cycles your disk can handle from the disk specs. My Seagate ST9120822A is rated to >600,000 cycles.

Find how many cycles your disk uses. You can use this simple script to get something like:

2008-07-30 09:24: 242613
2008-07-30 09:25: 242616
2008-07-30 09:26: 242618
2008-07-30 09:27: 242621
2008-07-30 09:28: 242623
2008-07-30 09:29: 242625
2008-07-30 09:30: 242627

(The script polls every minute)

Lower the usage with hdparm:

hdparm -B192 -S180 /dev/hda

Try different values for B in the range 128-255. Lower values means more power saving (and probably an increase in load cycles). -S sets the spindown time 180 -> 180x5 secs = 15 minutes.

I am not sure where the settings are changed by hardware/bios/os, but I reset from =/etc/acpi= in my action for lid close/open. Cron could also be used to reset it.