Github user fmthoma commented on a diff in the pull request: https://github.com/apache/flink/pull/6021#discussion_r189433306 --- Diff: flink-connectors/flink-connector-kinesis/src/main/java/org/apache/flink/streaming/connectors/kinesis/FlinkKinesisProducer.java --- @@ -326,6 +342,24 @@ private void checkAndPropagateAsyncError() throws Exception { } } + /** + * If the internal queue of the {@link KinesisProducer} gets too long, + * flush some of the records until we are below the limit again. + * We don't want to flush _all_ records at this point since that would + * break record aggregation. + */ + private void checkQueueLimit() { + while (producer.getOutstandingRecordsCount() >= queueLimit) { + producer.flush(); --- End diff -- So I'd suggest to add `producer.notifyAll()` to both `onSuccess()` and `onFailure()` in the callback, and replace the `Thread.sleep(500)` by `producer.wait(500)`. This way we re-check with every record sent out, or at most after 0.5 seconds.
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