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  1. MongoDB Database Tools
  2. TOOLS-1498

Stats collection has large playback performance impact

    • Type: Icon: Bug Bug
    • Resolution: Done
    • Priority: Icon: Major - P3 Major - P3
    • 3.4.1, 3.5.2
    • Affects Version/s: 3.4.0-rc0
    • Component/s: mongoreplay
    • None
    • Platforms 2016-11-21
    • v3.4

      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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            Assignee:
            matt.cotter Matt Cotter
            Reporter:
            bruce.lucas@mongodb.com Bruce Lucas (Inactive)
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              Created:
              Updated:
              Resolved: