druid/docs/design/peons.md

---
id: peons
title: "Peon service"
sidebar_label: "Peon"
---

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

## Configuration

For Apache Druid Peon configuration, see [Peon Query Configuration](../configuration/index.md#peon-query-configuration) and [Additional Peon Configuration](../configuration/index.md#additional-peon-configuration).

For basic tuning guidance for MiddleManager tasks, see [Basic cluster tuning](../operations/basic-cluster-tuning.md#task-configurations).

## HTTP endpoints

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

## Running

The Peon should seldom run separately from the MiddleManager, 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.