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Guozhang Wang commented on KAFKA-7192: -------------------------------------- Hello [~jonmbates] Thanks for reporting this issue. I've successfully reproduced this issue and found the root cause. I've submitted the PR and added a unit test to expose this issue, and confirmed that without the PR that unit test will fail. > State-store can desynchronise with changelog > -------------------------------------------- > > Key: KAFKA-7192 > URL: https://issues.apache.org/jira/browse/KAFKA-7192 > Project: Kafka > Issue Type: Bug > Components: streams > Affects Versions: 1.1.1 > Reporter: Jon Bates > Priority: Critical > > n.b. this bug has been verified with exactly-once processing enabled > Consider the following scenario: > * A record, N is read into a Kafka topology > * the state store is updated > * the topology crashes > h3. *Expected behaviour:* > # Node is restarted > # Offset was never updated, so record N is reprocessed > # State-store is reset to position N-1 > # Record is reprocessed > h3. *Actual Behaviour* > # Node is restarted > # Record N is reprocessed (good) > # The state store has the state from the previous processing > I'd consider this a corruption of the state-store, hence the critical > Priority, although High may be more appropriate. > I wrote a proof-of-concept here, which demonstrates the problem on Linux: > [https://github.com/spadger/kafka-streams-sad-state-store] -- This message was sent by Atlassian JIRA (v7.6.3#76005)