| --- |
| layout: doc_page |
| --- |
| |
| Peons |
| ----- |
| Peons run a single task in a single JVM. MiddleManager is responsible for creating Peons for running tasks. |
| Peons should rarely (if ever for testing purposes) be run on their own. |
| |
| #### JVM Configuration |
| Although peons inherit the configurations of their parent middle managers, explicit child peon configs in middlemanager can be set by prefixing them with: |
| |
| ``` |
| druid.indexer.fork.property |
| ``` |
| Additional peon configs include: |
| |
| |Property|Description|Default| |
| |--------|-----------|-------| |
| |`druid.peon.mode`|Choices are "local" and "remote". Setting this to local means you intend to run the peon as a standalone node (Not recommended).|remote| |
| |`druid.indexer.task.baseDir`|Base temporary working directory.|/tmp| |
| |`druid.indexer.task.baseTaskDir`|Base temporary working directory for tasks.|/tmp/persistent/tasks| |
| |`druid.indexer.task.hadoopWorkingPath`|Temporary working directory for Hadoop tasks.|/tmp/druid-indexing| |
| |`druid.indexer.task.defaultRowFlushBoundary`|Highest row count before persisting to disk. Used for indexing generating tasks.|50000| |
| |`druid.indexer.task.chathandler.type`|Choices are "noop" and "announce". Certain tasks will use service discovery to announce an HTTP endpoint that events can be posted to.|noop| |
| |
| If the peon is running in remote mode, there must be an overlord up and running. Running peons in remote mode require the following configurations: |
| |
| |Property|Description|Default| |
| |--------|-----------|-------| |
| |`druid.peon.taskActionClient.retry.minWait`|The minimum retry time to communicate with overlord.|PT1M| |
| |`druid.peon.taskActionClient.retry.maxWait`|The maximum retry time to communicate with overlord.|PT10M| |
| |`druid.peon.taskActionClient.retry.maxRetryCount`|The maximum number of retries to communicate with overlord.|10| |
| |
| #### Running |
| |
| The peon should very rarely ever be run independent of the middle manager. |
| |
| ``` |
| io.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. |
