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With the release of 2.0 Kafka Streams will introduce topology optimization, the goal of which is to reduce the footprint Kafka Streams creates especially with repartition and changelog topics. To that end, we would like to introduce a new config "enable.topology.optimization". The default value for this new configuration will be false. Kafka Streams needs this configuration to ensure backward compatibility.

Public Interfaces

There are no changes planned to public interfaces with this change.

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This KIP will add a new config "enable.topology.optimization" to the StreamsConfig class.  Setting ENABLE_TOPOLOGY_OPTIMIZATION to any String value will enable optimization, setting this configuration to null disables optimization and is the default setting.

public static final String ENABLE_TOPOLOGY_OPTIMIZATION = "enable.topology.optimization" 
private static final String ENABLE_TOPOLOGY_OPTIMIZATION_DOC = "A configuration telling Kafka Streams if it should optimize the topology, falsenull by default"

Compatibility, Deprecation, and Migration Plan

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