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  1. WiredTiger
  2. WT-10832

Investigate reconciliation split logic not creating reasonably sized pages

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    • Type: Icon: Improvement Improvement
    • Resolution: Unresolved
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: None
    • Component/s: None
    • StorEng - Defined Pipeline

      We have seen some recent evidence that WiredTiger is inefficiently laying data out on leaf pages. That is managed by the reconciliation split logic - we should review that logic looking for places where it might make poor decisions.

      Note: It's possible that the poor page layout is due to access patterns not reconciliation inefficiency. If data in a table is populated then a majority of data is selectively removed it could lead to a similar pattern of small leaf pages.

      The case in hand has pages with an average of 600 bytes of data, when leaf_page_max is configured to be 16KB. Durable history is enabled. It is on an index in MongoDB, which probably has small key/value pairs being randomly updated across the data, along with 5 minutes of pinned history.

            Assignee:
            backlog-server-storage-engines [DO NOT USE] Backlog - Storage Engines Team
            Reporter:
            alexander.gorrod@mongodb.com Alexander Gorrod
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              Created:
              Updated: