While investigating why my hard drive load cycle count was increasing, I observed my APM level gets reset each time I come out of Suspend on my Debian Jessie laptop running MATE:
$ sudo smartctl --get=apm /dev/sda
...
APM feature is: Disabled
$ sudo hdparm -I /dev/sda | grep level
Advanced power management level: disabled
$ sudo hdparm -B /dev/sda
/dev/sda:
APM_level = off
After putting the laptop into Suspend and then taking it out of Suspend, I have the following:
$ sudo hdparm -I /dev/sda | grep level
Advanced power management level: 128
$ sudo smartctl --get=apm /dev/sda
...
APM level is: 128 (minimum power consumption without standby)
$ sudo hdparm -B /dev/sda
/dev/sda:
APM_level = 128
I tried enabling the APM options in /etc/hdparm.conf
, but it didn't seem to help:
...
# -B apm setting
#apm = 255
apm = 255
# -B apm setting when on battery
#apm_battery = 127
apm_battery = 255
...
Then:
$ sudo /etc/init.d/hdparm restart
After putting the hard drive into Suspend and bringing it back out, I noticed the APM level is back to 128.
mateconf-editor
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