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  1. MariaDB Server
  2. MDEV-31075

KILL QUERY maintains nodes data consistency but breaks GTID sequence

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    Description

      GTID sequence drifts between Write node and appliers node by issueing some KILL QUERY statements on a Galera node which is operating user's transactions.
      Data consistency is maintained and wsrep_last_committed is in sync.

      NOTE: It's not always sufficient to issue one single KILL QUERY, I should do more fine grained research to determine what are the specific circumstances, in my current tests I reproduced it by killing some random mysqlslap queries.

      GTID sequence de-alignment breaks among others maxscale auto-failover.
      To make things more complicated in the current attached pictures test Writer is behind but in other tests Writer went ahead(see attached txt for 2nd test)

      Attachments

        1. 1_Starting_Condition.png
          516 kB
          Claudio Nanni
        2. 2_Starting_Coords_And_LastCommitted.png
          386 kB
          Claudio Nanni
        3. 3_AfterFirstPlainSlapTest.png
          388 kB
          Claudio Nanni
        4. 4_NextTestWillKillQueries.png
          538 kB
          Claudio Nanni
        5. 5_End_SameGaleraLastCommitted_SkippedGTIDonSlaveNodes.png
          391 kB
          Claudio Nanni
        6. Alternate_Test-galera_gtid_drift_kill_query.txt
          2 kB
          Claudio Nanni

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              janlindstrom Jan Lindström
              claudio.nanni Claudio Nanni
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                Resolved:

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