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I have a simple script to help me do some power saving:

echo 1 > /sys/module/snd_hda_intel/parameters/power_save
echo min_power > /sys/class/scsi_host/host0/link_power_management_policy
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs

I want this to run on every boot as root, tried running it by adding:

/bin/bash /root/



and also tried by adding following to root's crontab:

@reboot /bin/bash /root/

no use..

share|improve this question
Either method (/etc/rc.local or @reboot) should work. There should be something from cron in /var/log/syslog, and cron will send you a mail if the command produces any output such as an error message. Add set -x at the top of the script (just after the #! line) and try again. Check that the script works when you invoke it directly, of course. – Gilles Apr 21 '11 at 19:35

You can run the commands directly in rc.local instead of running a script. Just put

echo 1 > /sys/module/snd_hda_intel/parameters/power_save
echo min_power > /sys/class/scsi_host/host0/link_power_management_policy
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs

in rc.local.

share|improve this answer
tried, doesn't work. – Shoaibi Apr 22 '11 at 5:03
This is weird, does it work when you issue the commands directly? How do you verify that the commands don't work? – duenni Apr 22 '11 at 10:18
i cat the files and they don't contain the text there should be. Manually running them works though. – Shoaibi Apr 25 '11 at 6:40
Could you post the content of your rc.local? Also you could test if rc.local is executed at all put echo $(date) >> /var/ in it and check /var/ after reboot. Maybe the commands are not executed because there is something missing/not loaded when rc.local is running. You could try and put a sleep 10 at the beginning of the file... – duenni Apr 25 '11 at 9:10

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