partition question I'm using one topic, one partition, one consumer, Kafka client version is 0.10. I got two different results: If I paused partition first, then to produce a message and to invoke resume method. KafkaConsumer can poll the uncommitted message successfully. But If I produced message first and didn't commit its offset, then to pause the partition, after several seconds, to invoke the resume method. KafkaConsumer would not receive the uncommitted message. I checked it on Kafka server using kafka-consumer-groups.sh, it shows LOG-END-OFFSET minus CURRENT-OFFSET = LAG = 1. I have been trying to figure out it for two days, I repeated such tests a lot of times, the results are always like so. I need some suggestion or someone can tell me its Kafka's original mechanism.