Hi TaiJuWu, What would be the behavior if the application sends several records with different ack levels? The RPC support acks at the ProduceRequest, so common for several batches, might even be for different topic-partitions: https://cwiki.apache.org/confluence/display/KAFKA/A+Guide+To+The+Kafka+Protocol#AGuideToTheKafkaProtocol-ProduceAPI
LibRdKafka supports acks at the topic level, but then it does group ProduceRequest for different topics in a single request. That might lead to performance drawbacks in some cases (like many different topics used by a producer). Regards, Fred
