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  1. Couchbase Server
  2. MB-44109

[UI] - Visual query plan potentially misleading w.r.t. time spent in phases

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Details

    • Bug
    • Resolution: Fixed
    • Major
    • 7.0.0
    • 6.6.0
    • query_tools, UI
    • None
    • Untriaged
    • 1
    • Unknown

    Description

      In trying to diagnose where time was being spent. See attached screenshot of the visual plan and attached text of the plan.

      The visual plan seems to indicate that the "fetch" was where the longest time was being spent, but in fact it is the index scan where the bulk of time is being spent:

      #operator": "IndexScan3",
                            "#stats": {
                              "#itemsOut": 2170,
                              "#phaseSwitches": 77566,
                              "execTime": "485.536164ms",
                              "kernTime": "13.794827ms",
                              "servTime": "35.429536341s"
                            },
      

      and the fetch:

      "#operator": "Fetch",
                            "#stats": {
                              "#itemsIn": 2170,
                              "#itemsOut": 2170,
                              "#phaseSwitches": 80526,
                              "execTime": "644.873782ms",
                              "kernTime": "36.358946263s",
                              "servTime": "2.690582011s"
                            },
      

      Attachments

        1. image.png
          image.png
          155 kB
        2. image-2021-03-18-13-45-02-637.png
          image-2021-03-18-13-45-02-637.png
          36 kB
        3. plan-text.json
          11 kB
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            pierre.regazzoni Pierre Regazzoni
            perry Perry Krug
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            Dates

              Created:
              Updated:
              Resolved:

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