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  1. Core Server
  2. SERVER-47866

Secondary readers do not need to reacquire PBWM lock if there are catalog conflicts

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    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Major - P3
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 4.8.0
    • Component/s: None
    • Labels:
      None
    • Backwards Compatibility:
      Fully Compatible
    • Sprint:
      Execution Team 2020-09-21, Execution Team 2020-10-05
    • Linked BF Score:
      23

      Description

      When a read on a secondary uses kLastApplied/kNoOverlap and encounters a collection catalog conflict, it uses a trick to reacquire the PBWM lock and read without a timestamp.

      This was necessary because single-phase background index builds would timestamp writes at future timestamps that may never be seen on secondaries (i.e. "ghost timestamps"). This is not necessary now that simultaneous index builds are the only index builds in 4.5+.

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              Assignee:
              louis.williams Louis Williams
              Reporter:
              louis.williams Louis Williams
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                Updated:
                Resolved: