druid/extensions/graphite-emitter

introduction

This extension emits druid metrics to a graphite carbon server. Events are sent after been pickled; the size of the batch is configurable.

configuration

All the configuration parameters for graphite emitter are under druid.emitter.graphite.

property	description	required?	default
druid.emitter.graphite.hostname	The hostname of the graphite server.	yes	none
druid.emitter.graphite.port	The port of the graphite server.	yes	none
druid.emitter.graphite.batchSize	Number of events to send as one batch.	no	100
druid.emitter.graphite.eventConverter	Filter and converter of druid events to graphite event(please see next section).	yes	none
druid.emitter.graphite.flushPeriod	Queue flushing period in milliseconds.	no	1 minute
druid.emitter.graphite.maxQueueSize	Maximum size of the queue used to buffer events.	no	MAX_INT
druid.emitter.graphite.alertEmitters	List of emitters where alerts will be forwarded to.	no	empty list (no forwarding)

Druid to Graphite Event Converter

Graphite Event Converter defines a mapping between druid metrics name plus dimensions to a Graphite metric path. Graphite metric path is organized using the following schema: <namespacePrefix>.[<druid service name>].[<druid hostname>].<druid metrics dimensions>.<druid metrics name> Properly naming the metrics is critical to avoid conflicts, confusing data and potentially wrong interpretation later on.

Example druid.historical.hist-host1_yahoo_com:8080.MyDataSourceName.GroupBy.query/time:

• druid -> namespace prefix
• historical -> service name
• hist-host1.yahoo.com:8080 -> druid hostname
• MyDataSourceName -> dimension value
• GroupBy -> dimension value
• query/time -> metric name

We have two different implementation of event converter:

Send-All converter

The first implementation called all, will send all the druid service metrics events. The path will be in the form <namespacePrefix>.[<druid service name>].[<druid hostname>].<dimensions values ordered by dimension's name>.<metric> User has control of <namespacePrefix>.[<druid service name>].[<druid hostname>].

You can omit the hostname by setting ignoreHostname=true druid.SERVICE_NAME.dataSourceName.queryType.query.time

You can omit the service name by setting ignoreServiceName=true druid.HOSTNAME.dataSourceName.queryType.query.time

druid.emitter.graphite.eventConverter={"type":"all", "namespacePrefix": "druid.test", "ignoreHostname":true, "ignoreServiceName":true}

White-list based converter

The second implementation called whiteList, will send only the white listed metrics and dimensions. Same as for the all converter user has control of <namespacePrefix>.[<druid service name>].[<druid hostname>]. White-list based converter comes with the following default white list map located under resources defaultWhiteListMap.json

Although user can override the default white list map by supplying a property called mapPath. This property is a String containing the path for the file containing white list map Json object. For example the following converter will read the map from the file /pathPrefix/fileName.json.

druid.emitter.graphite.eventConverter={"type":"whiteList", "namespacePrefix": "druid.test", "ignoreHostname":true, "ignoreServiceName":true, "mapPath":"/pathPrefix/fileName.json"}

Druid emits a huge number of metrics we highly recommend to use the whiteList converter