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

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The MiddleManager service is a worker service that executes submitted tasks. MiddleManagers forward tasks to [Peons](../design/peons.md) that run in separate JVMs.
Druid uses separate JVMs for tasks to isolate resources and logs. Each Peon is capable of running only one task at a time, wheres a MiddleManager may have multiple Peons.

## 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, see the [Service status API reference](../api-reference/service-status-api.md#middlemanager).

## Running

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