kafka-streams-properties.adoc

Configuration Properties

Table 1. Configuration Properties

Name	Default Value	Description
application.id		Application ID, i.e. the identifier of a stream processing application. It must be unique within the Kafka cluster as it is used as the default client-id prefix, the group-id for membership management, and the changelog topic prefix. Use StreamsConfig.APPLICATION_ID_CONFIG to reference the property.
application.server	(empty)	A host:port pair pointing to an embedded user-defined endpoint (that can be used for discovering the locations of state stores in a single KafkaStreams application). Use StreamsConfig.APPLICATION_SERVER_CONFIG to reference the property. Used when StreamPartitionAssignor is requested to configure itself.
commit.interval.ms	100L when processing.guarantee is exactly_once (which is not by default) 30000L otherwise	Flush interval (in milliseconds), i.e. the time between persisting the position of a processor. Use StreamsConfig.COMMIT_INTERVAL_MS_CONFIG to reference the property.
num.stream.threads	1	The number of threads to execute stream processing.
poll.ms	100	Polling interval (in milliseconds), i.e. the time spent waiting in Consumer.poll (unless data is available in the buffer). If 0, returns immediately with any records that are available currently in the buffer, else returns empty. Must not be negative. Used when GlobalStreamThread is requested to initialize (which is right after KafkaStreams has been started) and creates a StateConsumer Used when StreamThread is created Use StreamsConfig.POLL_MS_CONFIG to reference the property.
processing.guarantee	at_least_once	Processing guarantee (aka Exactly-Once Support or EOS support) Possible values are: at_least_once (default) exactly_once Note exactly-once processing guarantee requires a Kafka cluster with at least three brokers (which is the recommended setting for production). For development you can change this by adjusting broker setting transaction.state.log.replication.factor. Use StreamsConfig.PROCESSING_GUARANTEE_CONFIG to reference the property.
state.cleanup.delay.ms	10 * 60 * 1000	The amount of time (in milliseconds) to wait before deleting state when a partition has migrated. Only state directories that have not been modified for at least state.cleanup.delay.ms will be removed.
state.dir	/tmp/kafka-streams	Path to the base directory for a state storage Used when StateDirectory is created Use StreamsConfig.STATE_DIR_CONFIG to reference the property.