mirror of https://github.com/apache/druid.git
52 lines
2.0 KiB
Markdown
52 lines
2.0 KiB
Markdown
---
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id: indexing-service
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title: "Indexing Service"
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---
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~ Licensed to the Apache Software Foundation (ASF) under one
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The Apache Druid indexing service is a highly-available, distributed service that runs indexing related tasks.
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Indexing [tasks](../ingestion/tasks.md) create (and sometimes destroy) Druid [segments](../design/segments.md). The indexing service has a master/slave like architecture.
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The indexing service is composed of three main components: a [Peon](../design/peons.md) component that can run a single task, a [Middle Manager](../design/middlemanager.md) component that manages Peons, and an [Overlord](../design/overlord.md) component that manages task distribution to MiddleManagers.
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Overlords and MiddleManagers may run on the same process or across multiple processes while MiddleManagers and Peons always run on the same process.
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Tasks are managed using API endpoints on the Overlord service. Please see [Overlord Task API](../operations/api-reference.md#tasks) for more information.
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![Indexing Service](../assets/indexing_service.png "Indexing Service")
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## Overlord
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See [Overlord](../design/overlord.md).
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## Middle Managers
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See [Middle Manager](../design/middlemanager.md).
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## Peons
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See [Peon](../design/peons.md).
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## Tasks
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See [Tasks](../ingestion/tasks.md).
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