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  1. Core Server
  2. SERVER-30724

Initial sync might miss ops that were in flight when it started

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    • Type: Icon: Bug Bug
    • Resolution: Fixed
    • Priority: Icon: Major - P3 Major - P3
    • 3.2.21
    • Affects Version/s: 3.0.15, 3.2.16
    • Component/s: Replication, Storage
    • Labels:
      None
    • Fully Compatible
    • ALL
    • Storage 2017-09-11

      When initial sync starts, the node reads the last oplog entry "A" from its sync source and uses that as its starting point when it applies operations in a later phase. Because such a read is not subject to oplog visibility rules (because it uses a reverse scanning cursor instead of a forward cursor), there could be uncommitted operations prior to "A" that affect documents after initial sync has already passed such documents by in its collection scan phase. Such changes would never be applied to the initial-syncing node.

            Assignee:
            judah.schvimer@mongodb.com Judah Schvimer
            Reporter:
            milkie@mongodb.com Eric Milkie
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              Created:
              Updated:
              Resolved: