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  1. Documentation
  2. DOCS-7979

Size and count in collection stats are persisted during checkpoints in WiredTiger

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    Details

    • Type: Task
    • Status: Closed
    • Priority: Major - P3
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 01112017-cleanup
    • Component/s: manual
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    • Last comment by Customer:
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      Description

      https://docs.mongodb.com/manual/reference/command/collStats/#unexpected-shutdown-and-count

      I reported some inaccurate information via DOCS-5682, saying that size and count is updated every 1000 document writes. As clarified in SERVER-24266, we update the in-memory cache every 1000 document writes, but the updates only become persistent when WiredTigerKVEngine::syncSizeInfo is called, most commonly every 60 seconds as part of WiredTigerKVEngine::haveDropsQueued.

      This means that number can drift much more in the event of an unclean shutdown (as much as 60 seconds worth of writes).

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              Assignee:
              ravind.kumar Ravind Kumar (Inactive)
              Reporter:
              pasette Daniel Pasette
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              Last commenter:
              Jonathan Dahl Jonathan Dahl
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                Created:
                Updated:
                Resolved:
                Days since reply:
                5 years, 22 weeks, 5 days ago
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