The Ubuntu Enterprise Cloud includes an innovative, integrated power management feature, which can provide some significant power savings in under-utilized clouds.
Prerequisites
- Your node(s) must support wake-on-lan, and have it enabled in the bios.
Each node runs a program called powernap, which attempt to do the following, in this specific order:
- /etc/powernap/action
- pm-suspend
- pm-hibernate
- poweroff The node should be able to execute at least one of these.
Enabling UEC Power Management
To enable UEC's Power Management, enable the POWERSAVE scheduling algorithm in your Cloud Controller's /etc/eucalyptus/eucalyptus.conf.
sudo sed -i "s/^SCHEDPOLICY=.*$/SCHEDPOLICY=POWERSAVE/" /etc/eucalyptus.conf sudo restart eucalyptus
Monitoring UEC Power Management
By default, Eucalyptus will wait for 300 seconds (5 minutes) of inactivity on a node before putting it to sleep.
You can monitor the state by watching the :
tail -f /var/log/eucalyptus/cc.log
You can watch the counter for each node, with messages like:
[Tue Nov 24 20:13:03 2009][010063][EUCADEBUG ] node 10.1.1.243 idle since 1259114895: (288/300) seconds
Once the requisite 300 idle seconds have elapse, you can see Eucalyptus sending the powernap signal to each node, with messages like this:
[Tue Nov 25 16:09:57 2009][017368][EUCADEBUG ] sending powerdown to node: 192.168.1.126, http://192.168.1.126:8775/axis2/services/EucalyptusNC