becketqin commented on pull request #12255:
URL: https://github.com/apache/flink/pull/12255#issuecomment-631167059


   @aljoscha Thanks for the review. I went through all the reported failures in 
the Jira ticket. It looks people are reporting two different issues. 
   1. The "producer already closed" error caused by the race condition in 
`StreamOperatorWrapper` that we are trying to fix in FLINK-16383. 
   2. The "does not host this topic-partition" error we are trying to fix here. 
   
   All the failures caused by issue 2 are either from 0.10 or 0.11 Kafka 
connectors, while the first issues are reported on all the versions. I think 
people are just adding comments to the same ticket once they see this test 
failed, regardless of the failure cause.
   
   That being said, theoretically speaking, using `KafkaAdminClient` to create 
topic does not 100% guarantee that a producer will not see the "does not host 
this topic-partition" error. This is because when the `AdminClient` can only 
guarantee the topic metadata information has existed in the broker to which it 
sent the `CreateTopicRequest`. When a producer comes at a later point, it might 
send `TopicMetdataRequest` to a different broker and that broker may have not 
received the updated topic metadata yet. But this is much unlikely to happen 
given the broker usually receives the metadata update at the same time. Having 
retries configured on the producer side should be sufficient to handle such 
cases. We can also do that for 0.10 and 0.11 producers. But given that we have 
the producer properties scattered over the places (which is something we 
probably should avoid to begin with), it would be simpler to just make sure the 
topic has been created successfully before we start the tests.


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