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  1. WiredTiger
  2. WT-8150

Poor search near performance if a lot of data are invisible

    • Type: Icon: Bug Bug
    • Resolution: Gone away
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: None
    • Component/s: None
    • None
    • 0
    • Storage - Ra 2021-11-15, Storage - Ra 2021-11-29, Storage - Ra 2022-01-24

      In the last step of search near, wiredtiger walks the cursor back and forth to find a visible value. If there are a lot of invisible data to the reader, the search near performs poorly. As for each invisible key it inspects, it needs to do a history store search to check if there is a visible version in the history store or not. And most of the time, it will find nothing there.

      Scope of the ticket:
      Brainstorm optimisations to improve the search near performance in this case and create separate tickets.

            Assignee:
            backlog-server-storage-engines [DO NOT USE] Backlog - Storage Engines Team
            Reporter:
            chenhao.qu@mongodb.com Chenhao Qu
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              Created:
              Updated:
              Resolved: