To use this extension, make sure to include statsd-emitter extension.
This extension emits druid metrics to a StatsD server. (https://github.com/etsy/statsd) (https://github.com/armon/statsite)
All the configuration parameters for the StatsD emitter are under druid.emitter.statsd.
| property | description | required? | default |
|---|---|---|---|
druid.emitter.statsd.hostname | The hostname of the StatsD server. | yes | none |
druid.emitter.statsd.port | The port of the StatsD server. | yes | none |
druid.emitter.statsd.prefix | Optional metric name prefix. | no | "" |
druid.emitter.statsd.separator | Metric name separator | no | . |
druid.emitter.statsd.includeHost | Flag to include the hostname as part of the metric name. | no | false |
druid.emitter.statsd.dimensionMapPath | JSON file defining the StatsD type, and desired dimensions for every Druid metric | no | Default mapping provided. See below. |
druid.emitter.statsd.blankHolder | The blank character replacement as statsD does not support path with blank character | no | “-” |
Each metric sent to StatsD must specify a type, one of [timer, counter, guage]. StatsD Emitter expects this mapping to be provided as a JSON file. Additionally, this mapping specifies which dimensions should be included for each metric. StatsD expects that metric values be integers. Druid emits some metrics with values between the range 0 and 1. To accommodate these metrics they are converted into the range 0 to 100. This conversion can be enabled by setting the optional “convertRange” field true in the JSON mapping file. If the user does not specify their own JSON file, a default mapping is used. All metrics are expected to be mapped. Metrics which are not mapped will log an error. StatsD metric path is organized using the following schema: <druid metric name> : { "dimensions" : <dimension list>, "type" : <StatsD type>, "convertRange" : true/false} e.g. query/time" : { "dimensions" : ["dataSource", "type"], "type" : "timer"}
For metrics which are emitted from multiple services with different dimensions, the metric name is prefixed with the service name. e.g. "coordinator-segment/count" : { "dimensions" : ["dataSource"], "type" : "gauge" }, "historical-segment/count" : { "dimensions" : ["dataSource", "tier", "priority"], "type" : "gauge" }
For most use-cases, the default mapping is sufficient.