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  1. WiredTiger
  2. WT-3499

Checkpoint can miss not yet committed item

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    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major - P3
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 3.2.17, 3.4.9, 3.5.12, WT3.0.0
    • Component/s: None
    • Labels:
      None
    • Sprint:
      Storage 2017-08-21
    • Backport Requested:
      v3.4, v3.2

      Description

      The new test in WT-3452 has been showing a problem where it is missing a few records but then later records exist in the table after recovery. This is not using any timestamps. What I see is that the missing record is the last record written into the log before the new checkpoint_start record (from WT-3440).

      What I believe is happening is that these records are written to the log first and then the checkpoint starts and writes its record after these records in the log, getting a later LSN. But the checkpoint doesn't write them out because the transactions are not yet resolved. After a crash, on recovery, we start at the checkpoint_start record, and never apply those, nor are they in the on-disk image.

      I'm able to reproduce on develop in about 100 iterations. I'm attempting to reproduce on 2.9.3 release before the start record was introduced.

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              • Assignee:
                sue.loverso Susan LoVerso
                Reporter:
                sue.loverso Susan LoVerso
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                Dates

                • Created:
                  Updated:
                  Resolved: