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Power management policy and hard disk lifetime

To save batteries'lifetime, hard disks can be shutdowned. By using hdparm, it's possible to specify the policy that hard drives should follow.

After reading the article It's confirmed: Gutsy is killing your HDD! on Plan├Ęte Beranger, I had a look to my hard drives and it seems that my laptop has the same issue:

# smartctl -A /dev/sda |grep -E "(Load_Cycle_Count|Power_On)"
  9      Power_On_Hours          0x0032   100   100   000    Old_age   Always       -       500
  193    Load_Cycle_Count        0x0032   076   076   000    Old_age   Always       -       49475
98cycles/hour, it seems to be quite a lot ... and can explain why I lost my previous hard disks some weeks ago after only two years of use. I don't think such a value can reduce the power consumption, just think about the peak of power needed each time the disk is turned on ...

As said previously, the way the hard disk behaves can be altered with hdparm using the option -B (with a parameter from 1 to 255, 225 to disablee the power management)

# hdparm -B255 /dev/sda

/dev/sda:
 setting Advanced Power Management level to disabled
After setting this value, Load_Cycle_Count doesn't grow up anymore.
The value is not changed after a reboot but it looks like Windows changes it. It is maybe stored on the bios because I never used Windows on my new drive. This should be confirmed.


Last update: 2007/10/29