collectd-sml: collectd plugin to receive data from SML-capable energy meters

jSML is a Java library implementing the Smart Message Language (SML).

collectd-sml receives SML data files from an electronic energy meter and makes it available to collectd via the collectd Java plugin interface.

The fields in collectd’s data packets are set as follows:

• hostname = [set at compile-time]
• plugin = smlreceiver
• plugin_instance = [SML server ID]
• type = watts or watt_hours
• type_instance = [OBIS code]

Context

This software has been developed in the context of the bachelor's thesis "Measuring, Visualizing, and Optimizing the Energy Consumption of Computer Clusters". The thesis provides more information about the hardware and software environment that this plugin was designed to be used in.

Setup

All new data types must be manually added to Collectd's type list (the path to which is specified in collectd.conf). For most values from the SML energy meter, a simple positive-only gauge should suffice, e.g.

watts       value:GAUGE:0:U
watt_hours  value:GAUGE:0:U

To load this plugin into a collectd instance, a configuration stanza similar to the following has to be added to collectd.conf:

<Plugin "java">
  JVMArg "-Djava.class.path=/opt/collectd/lib/collectd/bindings/java"
  LoadPlugin "de.voidptr.collectd_plugins.SMLReceiver"
  <Plugin "de.voidptr.collectd_plugins.SMLReceiver">
    SerialPort = "/dev/ttyAMA0"
  </Plugin>
</Plugin>

Licensing

jSML v1.0.17 was released under the GNU Lesser General Public License v2.1 (see [licenses/COPYING.LESSER]) thus requiring all modifications to be licensed under the LGPL v2.1 as well.

Where legally possible, new additions (such as src/de/voidptr/collectd_plugins/SMLReceiver.java) are licensed under the Apache License v2.0.

Note that as of v1.1.0 (19-Jul-2017), jSML is licensed under the Mozilla Public License v2.0.