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  1. Core Server
  2. SERVER-20299

Delete KEEP_MUTATIONS stage

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    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Major - P3
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 4.1.2
    • Component/s: Querying
    • Labels:
      None
    • Backwards Compatibility:
      Fully Compatible
    • Sprint:
      Quint 9 09/18/15, QuInt E (01/11/16), Query 2018-07-30, Query 2018-08-13

      Description

      The KEEP_MUTATIONS query execution stage was originally intended to make a best effort at returning concurrently modified documents from queries against a node configured to use the MMAP storage engine. However, the necessity of this stage is dubious. My reading of the implementation is that is is only necessary if buffered documents are concurrently updated during the execution of an index intersection plan.

      Deleting KEEP_MUTATIONS would be welcome code removal that would help to simplify some tricky pieces of the query planner and query execution engine.

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              Assignee:
              david.storch David Storch
              Reporter:
              david.storch David Storch
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                Updated:
                Resolved: