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Matthias J. Sax commented on KAFKA-4325: ---------------------------------------- [~vvcephei], I think, this is resolved with the new strict enforcement of retention time you worked on? Can you confirm? Do we have a ticket for it so we can resolve this as "included in KAFKA-xxx" ? > Improve processing of late records for window operations > -------------------------------------------------------- > > Key: KAFKA-4325 > URL: https://issues.apache.org/jira/browse/KAFKA-4325 > Project: Kafka > Issue Type: Improvement > Components: streams > Reporter: Matthias J. Sax > Priority: Minor > > Windows are kept until their retention time passed. If a late arriving record > is processed that is older than any window kept, a new window is created > containing this single late arriving record, the aggregation is computed and > the window is immediately discarded afterward (as it is older than retention > time). > This behavior might case problems for downstream application as the original > window aggregate might we overwritten with the late single-record- aggregate > value. Thus, we should rather not process the late arriving record for this > case. > However, data loss might not be acceptable for all use cases. In order to > enable the use to not lose any data, window operators should allow to > register a handler function that is called instead of just dropping the late > arriving record. -- This message was sent by Atlassian JIRA (v7.6.3#76005)