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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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          Issue Links

          is depended on by

          Task - A task that needs to be done. SERVER-38341 Remove Parallel Batch Writer Mutex

          • Major - P3 - Major loss of function.
          • Open
          is duplicated by

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-49285 Support getMore on snapshot cursor even after unrelated index is created or dropped

          • Major - P3 - Major loss of function.
          • Closed
          is related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-48518 Rollback via refetch (EMRC = false) can make readers to see the rolled back data even after the rollback node catches up to primary.

          • Major - P3 - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-49285 Support getMore on snapshot cursor even after unrelated index is created or dropped

          • Major - P3 - Major loss of function.
          • Closed
          related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-51703 index_secondary_wait_for_commit.js - IndexBuildTest.assertIndexes() sees different server state from IndexBuildTest.getIndexBuildOpId()

          • Major - P3 - Major loss of function.
          • Closed

            Activity

              People

              Assignee:
              louis.williams Louis Williams
              Reporter:
              louis.williams Louis Williams
              Participants:
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                Dates

                Created:
                Updated:
                Resolved: