mirror of https://github.com/apache/druid.git
79 lines
3.0 KiB
Markdown
79 lines
3.0 KiB
Markdown
---
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layout: doc_page
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title: "Tasks Overview"
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---
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# Tasks Overview
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Tasks are run on MiddleManagers and always operate on a single data source.
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Tasks are submitted using POST requests to the Overlord. Please see [Overlord Task API](../operations/api-reference.html#overlord-tasks) for API details.
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There are several different types of tasks.
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## Segment Creation Tasks
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### Hadoop Index Task
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See [batch ingestion](../ingestion/hadoop.html).
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### Native Index Tasks
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Druid provides a native index task which doesn't need any dependencies on other systems.
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See [native index tasks](./native_tasks.html) for more details.
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<div class="note info">
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Please check [Hadoop-based Batch Ingestion VS Native Batch Ingestion](./hadoop-vs-native-batch.html) for differences between native batch ingestion and Hadoop-based ingestion.
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</div>
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### Kafka Indexing Tasks
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Kafka Indexing tasks are automatically created by a Kafka Supervisor and are responsible for pulling data from Kafka streams. These tasks are not meant to be created/submitted directly by users. See [Kafka Indexing Service](../development/extensions-core/kafka-ingestion.html) for more details.
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### Stream Push Tasks (Tranquility)
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Tranquility Server automatically creates "realtime" tasks that receive events over HTTP using an [EventReceiverFirehose](../ingestion/firehose.html#eventreceiverfirehose). These tasks are not meant to be created/submitted directly by users. See [Tranquility Stream Push](../ingestion/stream-push.html) for more info.
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## Compaction Tasks
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Compaction tasks merge all segments of the given interval. Please see [Compaction](../ingestion/compaction.html) for details.
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## Segment Merging Tasks
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<div class="note info">
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The documentation for the Append Task, Merge Task, and Same Interval Merge Task has been moved to <a href="../ingestion/misc-tasks.html">Miscellaneous Tasks</a>.
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</div>
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## Kill Task
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Kill tasks delete all information about a segment and removes it from deep storage.
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Please see [Deleting Data](../ingestion/delete-data.html) for details.
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## Misc. Tasks
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Please see [Miscellaneous Tasks](../ingestion/misc-tasks.html).
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## Task Locking and Priority
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Please see [Task Locking and Priority](../ingestion/locking-and-priority.html).
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