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  1. Core Server
  2. SERVER-55030

Remove mutexes that serialize secondary and majority read operations

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Details

    • Improvement
    • Status: Closed
    • Major - P3
    • Resolution: Fixed
    • None
    • 5.3.0
    • None
    • Fully Compatible
    • v4.4
    • Execution Team 2021-11-29, Execution Team 2021-12-13, Execution Team 2021-12-27, Execution Team 2022-01-10, Execution Team 2022-01-24, Execution Team 2022-02-07
    • 135

    Description

      MongoDB serializes the creation of new WiredTiger transactions for local secondary reads (i.e. lastApplied reads) and readConcern: majority reads.

      WT-6709 recently addressed performance problems in the WiredTiger timestamp queues that should make these mutexes unnecessary. Investigate removing both of these mutexes to potentially support higher read throughput.

      See SERVER-51041 for more details.

      Attachments

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        Issue Links

          causes

          Bug - A problem which impairs or prevents the functions of the product. SERVER-63244 Majority reads must round their read timestamp up to the oldest timestamp

          • Major - P3 - Major loss of function.
          • Closed
          is depended on by

          Task - A task that needs to be done. SERVER-55024 Complete TODO listed in WT-6709

          • Major - P3 - Major loss of function.
          • Closed
          is related to

          Improvement - An improvement or enhancement to an existing feature or task. WT-9074 Reconsider spinlocks in transaction ID allocation path

          • Major - P3 - Major loss of function.
          • Open
          related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-51041 Throttle starting transactions for secondary reads

          • Major - P3 - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. WT-6709 Remove timestamp queues that used to store read/durable timestamps

          • Major - P3 - Major loss of function.
          • Closed

          Activity

            People

              daniel.gomezferro@mongodb.com Daniel Gomez Ferro
              louis.williams@mongodb.com Louis Williams
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              Dates

                Created:
                Updated:
                Resolved: