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  1. MongoDB ETL Tools
  2. TOOLS-1498

Stats collection has large playback performance impact

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    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major - P3
    • Resolution: Fixed
    • Affects Version/s: 3.4.0-rc0
    • Fix Version/s: 3.4.1, 3.5.2
    • Component/s: mongoreplay
    • Labels:
      None
    • Backport Requested:
      v3.4
    • Sprint:
      Platforms 2016-11-21

      Description

      FTDC timeseries data for both the recording and playback phases:

      • A-C: record phase
        • A-B: 8 threads each inserting 500 k empty documents into a single collection in batches of 1000
        • B-C: 1 thread doing a collection scan
      • D-G: playback phase
        • D-F: inserts - playback of A-B. Note how the rate of inserts drops about halfway through, by about a factor of 2, and the inserts don't end until F, overlapping the reads, unlike during the record phase
        • E-G: reads - playbck of B-C. Note that this appears to begin at about the right time corresponding to B during the recording, but unlike during the recording, on playback this begins before the inserts have ended.

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        2. longer.png
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        3. varies.png
          varies.png
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          Activity

            People

            • Assignee:
              matt.cotter Matt Cotter
              Reporter:
              bruce.lucas Bruce Lucas
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              Dates

              • Created:
                Updated:
                Resolved: