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partition.availability.timeout.ms.  The default would be 0.  If the value is greater than 0 and adaptive partitioning is enabled, and the broker cannot accept a produce request to the partition for partition.availability.timeout.ms milliseconds, the partition is marked as not available.  If the value is 0, this logic is disabled.

Proposed Changes

This is the default partitioning logic for messages without keys, that substitutes the corresponding logic implemented in the default partitioner.  The default partitioner now can return -1 for messages without keys so that default partitioning logic can be executed.

Uniform Sticky Batch Size

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