I have installed TLP on my notebook with Ubuntu 14.04 to extend my battery life. Before using TLP I had
pm-utils installed with some custom scripts. Both extended my battery life by over 100%, however TLP almost didn’t need any configuration to achieve this.
However, I got one problem after installing TLP: Ubuntu wouldn’t suspend anymore. I was sure that it was still working just a day ago. If I click suspend, the screen goes blank for just a second and then I’m at the lock screen. The power LED doesn’t turn off, it just looks as if I accidentally clicked the log out button.
I’ve tried many workarounds, like this one on Ask Ubuntu. All other workarounds were nearly the same, and they all didn’t work for me.
So I started trying to fix the issue by myself.
If I executed
echo mem > /sys/power/state or
echo disk > /sys/power/state my notebook would suspend and resume as it should. So the suspend itself was working, but something was interrupting the suspend process before the notebook would actually suspend. It couldn’t be a wakeup call of any device, because I already disabled all wakeup devices.
/var/log/kern.log but they didn’t contain any useful information. They only told me that my WiFi adapter was disconnecting to prepare my notebook for the suspend, to immediately connect again.
Then I checked
/var/log/pm-suspend.log. At first it looked all okay to me. Then I saw the following:
Running hook /etc/pm/sleep.d/10-laptop-mode-tools suspend suspend: /etc/pm/sleep.d/10-laptop-mode-tools: 6: /etc/pm/sleep.d/10-laptop-mode-tools: /etc/init.d/laptop-mode: not found /etc/pm/sleep.d/10-laptop-mode-tools suspend suspend: Returned exit code 127. Wed Apr 23 15:27:19 CEST 2014: Inhibit found, will not perform suspend Wed Apr 23 15:27:19 CEST 2014: Running hooks for resume
It couldn’t find
laptop-mode-tools anymore, which I had to remove in order to use TLP, so it just aborted the whole suspend process.
/etc/pm/sleep.d/10-laptop-mode-tools everything was working as it should again.
Note: I recommend you to make a backup of the script first (copy it to your Documents directory using
sudo cp /etc/pm/sleep.d/10-laptop-mode-tools ~/Documents/) so you can always copy it back if you have to.
So, if you’re having this issue too, just execute
sudo rm /etc/pm/sleep.d/10-laptop-mode-tools.