Broker

For basic tuning guidance for the Broker process, see .

HTTP endpoints

The Broker is the process to route queries to if you want to run a distributed cluster. It understands the metadata published to ZooKeeper about what segments exist on what processes and routes queries such that they hit the right processes. This process also merges the result sets from all of the individual processes together. On start up, Historical processes announce themselves and the segments they are serving in Zookeeper.

Running

To determine which processes to forward queries to, the Broker process first builds a view of the world from information in Zookeeper. Zookeeper maintains information about Historical and streaming ingestion processes and the segments they are serving. For every datasource in Zookeeper, the Broker process builds a timeline of segments and the processes that serve them. When queries are received for a specific datasource and interval, the Broker process performs a lookup into the timeline associated with the query datasource for the query interval and retrieves the processes that contain data for the query. The Broker process then forwards down the query to the selected processes.

Caching