Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-88415

Address instability in metrics for $limit queries on sharded collections

    • Type: Icon: Task Task
    • Resolution: Unresolved
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: None
    • Component/s: None
    • Query Integration

      If a query contains a $limit and involves a sharded collection, the query can terminate (that is, return the final response with cursor ID 0) before receiving all responses from all shards. This means the metrics will be written without considering those metrics.

      This race creates the potential for instability in the metrics where different runs of the same query could have slightly different metrics. Note that there is a limit to the inaccuracy (one batch per shard).

            colby.ing@mongodb.com Colby Ing
            ryan.berryhill@mongodb.com Ryan Berryhill
            0 Vote for this issue
            4 Start watching this issue