I recently began using the exactly-once processing semantic with the Kafka 0.11 producer in Flink 1.4.2. It's been working great!
Are Kafka transactions committed when creating a Flink savepoint? How does this affect the recovery behavior in Flink if, before the completion of the next checkpoint, the application is restarted and restores from a checkpoint taken before the savepoint? It seems like this might lead to the Kafka producer writing a message multiple times with different committed Kafka transactions. -- Scott Kidder
