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I'm trying to compare the differences between how power management is handled on battery and when plugged in. As a result I want to look at the config files for the two instances. Thanks in advance.

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up vote 2 down vote accepted

hdparm is the command to get and set hard disk parameters.

hdparm is a command line utility for the Linux and Windows operating systems to set and view ATA hard disk drive hardware parameters. It can set parameters such as drive caches, sleep mode, power management, acoustic management, and DMA settings. GParted and Parted Magic both include hdparm.

hdparm has to be run with root privileges, otherwise it will either not be found or the requested actions will not be executed properly.

Some examples:

Display information of the hard drive:

hdparm -I /dev/sda

Turn on DMA for the first hard drive:

hdparm -d1 /dev/sda

Test cache read performance of the first hard drive:

hdparm -t /dev/sda

Enable energy saving spindown after inactivity (24*5=120 seconds):

hdparm -S 24 /dev/sda

To retain hdparm settings after a software reset, run:

hdparm -K 1 /dev/sda

Enable read-ahead:

hdparm -A 1 /dev/sda

If the disk is constantly too noisy, you can change its acoustic management at the cost of read/write performance:

hdparm -M 128 /dev/sda

External links with more examples:

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dconf shows no hdd configs or parameters – Mysterio Aug 28 '12 at 22:23
I just edited the question – Mysterio Aug 29 '12 at 11:59
Yeah this is it but one more question, will this conflict with laptop_mode tools? – Mysterio Aug 30 '12 at 5:52
I do not think 12.04 has laptop_tools? I faintly remember that it is obsolete. @Mysterio – Rinzwind Aug 30 '12 at 8:26
@Mysterio… – Rinzwind Aug 30 '12 at 8:27

This is not what you are looking for but if you are trying to control your laptop, you can always install Jupiter

sudo apt-add-repository ppa:webupd8team/jupiter
sudo apt-get update
sudo apt-get install jupiter


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I already have Jupiter installed and enabled. Thanks anyway – Mysterio Aug 28 '12 at 22:11

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