ericsyh opened a new issue #13823: URL: https://github.com/apache/pulsar/issues/13823
**Describe the bug** Created a more clear issue about https://github.com/apache/pulsar/issues/12759. In my current test found, if i create a producer to produce to with no dispatch limit while create a consumer to consumer with slow rate (set a 1 second sleep in message receive): * If i use a Latest position to consume, the consumer will miss some messages after the consumer transter the cluster. * If i use a Earliest postition to consume, the consumer will consume from beginning after the consumer transfer the cluster. And the weird thing is if i remove the 1 second sleep in consumer or i move the 1 second sleep from consumer to producer, there is no indeviduallyDeleteMessage in the topics. It looks like when the consumer is much slower than the producer, this issue will come. **To Reproduce** Steps to reproduce the behavior: 1. Start the producer without dispatch limit to Cluster A 2. Start the consumer with 1 second limit to consume to Cluster A 3. Stop the consumer after several consumes and acks are sent. 4. Transfer the consumer to Cluster B, and check the messageID the consumer got. 5. You can test the Latest position and Earliest position. **Expected behavior** No matter set the Latest position or Earliest position, the consume position should be continuous after transfer to the Cluster B. **Screenshots** This is a screenshot of consume with latest potision after the cluster transfer, you can see that some messages were missed.  **Additional context** Pulsar 2.8.1 These are test codes i used. [pulsar-client-go-demo.zip](https://github.com/apache/pulsar/files/7893596/pulsar-client-go-demo.zip) [consumer.java.zip](https://github.com/apache/pulsar/files/7893597/consumer.java.zip) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
