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  1. MongoDB Database Tools
  2. TOOLS-3761

Investigate changes in SERVER-100907: Only output 'reshardBlockingWrites' event when 'showSystemEvents' is true instead of when 'showMigrationEvents' is true

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    • Type: Icon: Investigation Investigation
    • Resolution: Won't Do
    • Priority: Icon: Major - P3 Major - P3
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    • Affects Version/s: None
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    • Tools and Replicator

      Original Downstream Change Summary

      Starting in 8.1, if there is an open $changeStream cursor with 'showSystemEvents': true while resharding is running:

      • If it is a cursor against a mongos, it would output a 'reshardBlockingWrites' event per donor shard.
      • If it is a cursor on a shardsvr mongod and if that shard is a donor in that resharding operation, it would output a 'reshardBlockingWrites' event for each recipient.  

        Description of Linked Ticket

      The new "reshardingBlockingWrites" event (SERVER-98981) is currently fromMigrate: true event so in SERVER-98584 we need to open a change streams cursor with showMigrationEvents: true but that has the unwanted effect of capturing deletes of orphan documents. Hiding the reshardBlockingWrites event behind showSystemEvents instead of showMigrationEvents allows the change streams monitor to see the reshardBlockingWrites without seeing the orphan docs deletes.

            Assignee:
            Unassigned Unassigned
            Reporter:
            backlog-server-pm Backlog - Core Eng Program Management Team
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              Created:
              Updated:
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