In some of our projects we need to understand the energy consumption of our servers in an Openstack cluster. The first step in this process was to collect energy consumption data from our IBM servers; we stored this in Ceilometer for further study. In this blog post we will cover how we do this.
First, Kwapi 101.
Kwapi is a part of the openstack ecosystem (perhaps a little peripheral) which is focused on collecting energy data. It has pretty good integration with Ceilometer which enables the energy data to be stored there.
Kwapi is architected in such a way that individual drivers listen to a specific wattmeter – a wattmeter can be a physical energy meter with a wifi interface or connected to ipmi, i.e. any kind of device that measures energy consumption. The drivers then pass the information on to plug-ins. These are the API, the forwarder and the RRD plugin which is the visualization plugin that provides a web interface with power consumption graphs.