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  1. Core Server
  2. SERVER-82899

Investigate SBE bucket level filters being slower than classic

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Details

    • Icon: Task Task
    • Resolution: Fixed
    • Icon: Major - P3 Major - P3
    • 7.3.0-rc0
    • None
    • None
    • None
    • Query Execution
    • Fully Compatible
    • 35

    Description

      The following agg pipeline on the TSBS dataset is ~30% slower in SBE with block processing than it is in classic.

      [
        {
          $match:
            {
              $and:
                [
                  { usage_user: { $gte: 0, $lt: 20 } },
                  { usage_system: { $gte: 20, $lt: 35 } },
                  { usage_idle: { $gte: 35, $lt: 50 } },
                  { usage_nice: { $gte: 50, $lt: 65 } },
                  { usage_iowait : { $gte: 65, $lt: 80 } },
                  { usage_steal: { $gte: 80, $lt: 90 } },
                  { usage_guest: { $gte: 90, $lt: 100 } },
                ],
            },
        },
        { $count: "count" }
      ]
      

      This should only be investigated once the linked issue is closed, since SBE block processing will currently unpack every bucket which makes it orders of magnitude slower than classic.

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            ian.boros@mongodb.com Ian Boros
            parker.felix@mongodb.com Parker Felix
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              Created:
              Updated:
              Resolved: