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  1. Kafka
  2. KAFKA-8001

AlterLogDirs: Fetch from future replica stalls when local replica becomes a leader

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    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Critical
    • Resolution: Duplicate
    • Affects Version/s: 2.1.0, 2.1.1
    • Fix Version/s: None
    • Component/s: core
    • Labels:
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      Description

      With KIP-320, fetch from follower / future replica returns FENCED_LEADER_EPOCH if current leader epoch in the request is lower than the leader epoch known to the leader (or local replica in case of future replica fetching). In case of future replica fetching from the local replica, if local replica becomes the leader of the partition, the next fetch from future replica fails with FENCED_LEADER_EPOCH and fetching from future replica is stopped until the next leader change. 

      This is a further burden operationally because log dir movement also disables log cleaning, meaning the original compacted partition that the user may want to move continues to grow unbounded

      Proposed solution: on local replica leader change, future replica should "become a follower" again, and go through the truncation phase. Or we could optimize it, and just update partition state of the future replica to reflect the updated current leader epoch. 

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              • Assignee:
                hachikuji Jason Gustafson
                Reporter:
                apovzner Anna Povzner
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                  Updated:
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