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  1. Lustre
  2. LU-8379

Possible badness with VBR and lock replay

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    • Bug
    • Resolution: Not a Bug
    • Minor
    • None
    • None
    • None
    • 3
    • 9223372036854775807

    Description

      As part of working on LU-8347, Jinshan raises some valid points I think.

      Let's say we have a VBR enabled system, recovery completed, but a client failed to join that had outstanding write locks and some dirty data.

      Now before this client rejoins, another client reads some data from a file that was modified (but not yet replayed) but this first client.

      questions:
      1. when the first client reconnect, would it be accepted (file version is not changed because there were no writes, so I think YES?)
      2. when it is accepted - that means second client actually accessed stale data - this is bad, right?
      3. As part of read second client also obtained some read locks on the data that client one is going to change - this is not good.
      4. What happens with replayed locks from client 1 in presence of already granted conflicted write locks?
      5. In fact if somebody has a write lock on a file - that does not change file version yet, right? Only writes do - so what's to prevent conflicting writes to be in flight for such files?

      I am capturing this here to better understand all these scenarios before categorizing this with a priority accordingly.

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            wc-triage WC Triage
            green Oleg Drokin
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              Updated:
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