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Peon service

docs/design/peons.md

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The Peon service is a task execution engine spawned by the Middle Manager. Each Peon runs a separate JVM and is responsible for executing a single task. Peons always run on the same host as the Middle Manager that spawned them.

Configuration

For Apache Druid Peon configuration, see Peon Query Configuration and Additional Peon Configuration.

For basic tuning guidance for Middle Manager tasks, see Basic cluster tuning.

HTTP endpoints

Peons run a single task in a single JVM. The Middle Manager is responsible for creating Peons for running tasks. Peons should rarely run on their own.

Running

The Peon should seldom run separately from the Middle Manager, except for development purposes.

org.apache.druid.cli.Main internal peon <task_file> <status_file>

The task file contains the task JSON object. The status file indicates where the task status will be output.