Statsd Daemon Usage¶
What Is It?¶
Statsd is a network daemon that listens for statistics sent over the network using TCP or UDP, and then sends aggregates to another backend.
Gnocchi provides a daemon that is compatible with the statsd protocol and can listen to metrics sent over the network, named gnocchi-statsd.
How Does It Work?¶
In order to enable statsd support in Gnocchi, you need to configure the [statsd] option group in the configuration file. You need to provide a resource ID that will be used as the main generic resource where all the metrics will be attached, a user and project id that will be associated with the resource and metrics, and an archive policy name that will be used to create the metrics.
All the metrics will be created dynamically as the metrics are sent to gnocchi-statsd, and attached with the provided name to the resource ID you configured.
The gnocchi-statsd may be scaled, but trade-offs have been made due to the nature of the statsd protocol. That means that if you use metrics of type counter or sampling (c in the protocol), you should always send those metrics to the same daemon – or not use them at all. The other supported types (timing and gauges) do not suffer this limitation, but be aware that you might have more measures than expected if you send the same metric to different gnocchi-statsd servers, as neither their cache nor their flush delay are synchronized.
The statsd protocol support is incomplete: relative gauge values with +/- and sets are not supported yet.