Eliminate schema lock from layered cursor open

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    • Storage Engines, Storage Engines - Foundations
    • SE Foundations - 2025-08-15, SE Foundations - 2025-08-29
    • 3

      Opened a layered cursor currently takes the schema lock. 

      I assume this is needed to ensure consistency across the layered table's constituent tables. 

      We should investigate whether it is possible to do this locking/coordination at the level of the layered table's dhandle rather than requiring a global lock. 

      Currently this is especially painful since we don't cache layered cursors, leading to benchmarks showing 50,000+ schema lock acquisitions per second. But even when we get the cursor caching properly implemented (WT-14542), it would be better to avoid a global lock if we don't need it.

        1. image-2025-07-17-14-49-16-036.png
          image-2025-07-17-14-49-16-036.png
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            Assignee:
            Jie Chen
            Reporter:
            Keith Smith
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              Created:
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