Kafka Producer : Required properties
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When a producer record has been assigned to a partition through the partitioner, it will get handed over to a RecordAccumulator, where it will be added to a collection of record batch objects for each topic partition combination needed by the producer instance. Finally, record object will be sent off to the brokers.
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Each record batch has a limit of how many ProducerRecords can be buffered. the limit is not based on the number of records, but by a configuration setting named batch.size. Across all buffers, there is a configuration setting (buffer.memory) for how much memory can be user used to buffer records waiting to be sent to the brokers.
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