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Change the behavior of the default partitioner in the no explicit partition, key = null case. Choose the “sticky” partition for the given topic. The “sticky” partition is changed when the record accumulator is allocating a new batch for a topic on a given partition.

A new partitioner will be created to allow sticky partitioning on all records, even those that have non-null keys. This will mirror how the RoundRobinPartitioner uses the round robin partitioning strategy for all records, including those with keys.

Compatibility, Deprecation, and Migration Plan

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