Current implementation will flush the buffer in any case every put call received by Kafka Connect.

The consequence is that  batch.size will not be honored when consumer.max.poll.records < batch.size.

We want to eliminate this limitation adding a heartbeat thread that will send messages to a dedicated topic so that Kafka is forced to call the connector put method. When the connector receive a message from heartbeat  the buffer will be flushed. 

See DatabaseHeartbeatImpl for reference.