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Bruno Cadonna commented on KAFKA-19442: --------------------------------------- [~juned] did you verify if KAFKA-16017 might be cause of the behavior you saw? If it is, we can close this ticket as duplicate. > Kafka Streams state store used an outdated value when reducing records, > resulting in incorrect output. > ------------------------------------------------------------------------------------------------------ > > Key: KAFKA-19442 > URL: https://issues.apache.org/jira/browse/KAFKA-19442 > Project: Kafka > Issue Type: Bug > Components: streams > Reporter: juned > Priority: Major > > We observed a case where a reduce operation used an older version of the > store value instead of the latest when processing a new input. > Below i am describing the sequence of input and its outcome in changelog and > output topic > Lets see currently there is a key,value pair M0, in changelog & output Topic. > and u1,u2,u3 updates are received for the same key in the same order. > For u1,u2 all are fine > But For u3 update , Changelog topic has the *expected Outcome* but Output > topic has *incorrect* data. > > *{*}Sequence:{*}* > |Step|Reduction |ChangelogTopic|OutputTopic | > |------ |----------------------------|-------------------|-------------| > |Initial |M0 |M0 | > |u1 |M1 = reduce(M0, u1) |M1 |M1 | > |u2 |M2 = reduce(M1, u2) |M2 |M2 | > |u3 |M3 = reduce(M2, u3) |M3 |❌ Actually: > reduce(M1, u3) | > > Environment: > - Kafka-clients:3.5.1 > - kafka-streams:3.5.1 -- This message was sent by Atlassian Jira (v8.20.10#820010)