---
id: middlemanager
title: "MiddleManager service"
---

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### Configuration

For Apache Druid MiddleManager service configuration, see [MiddleManager and Peons](../configuration/index.md#middlemanager-and-peons).

For basic tuning guidance for the MiddleManager service, see [Basic cluster tuning](../operations/basic-cluster-tuning.md#middlemanager).

### HTTP endpoints

For a list of API endpoints supported by the MiddleManager, please see the [Service status API reference](../api-reference/service-status-api.md#middlemanager).

### Overview

The MiddleManager process is a worker process that executes submitted tasks. Middle Managers forward tasks to Peons that run in separate JVMs.
The reason we have separate JVMs for tasks is for resource and log isolation. Each [Peon](../design/peons.md) is capable of running only one task at a time, however, a MiddleManager may have multiple Peons.

### Running

```
org.apache.druid.cli.Main server middleManager
```