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  1. MariaDB Server
  2. MDEV-37244

buf_read_page() should return a buffer-fixed block

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Details

    • Related to performance
    • When a page needs to be read into the InnoDB buffer pool, concurrent access to the page will avoid some hash table lookup and busy waiting.
    • Q4/2025 Server Maintenance

    Description

      Every caller of buf_read_page() is expecting to gain access to the block. If that function returned a buffer-fixed block descriptor, we could avoid some busy work, such as a redundant lookup of buf_pool.page_hash.

      This change was initially part of the 11.4 development version of MDEV-34431, but there are some issues with it, apparently some hangs due to not released buffer-fix under some special circumstances. In my own performance testing yesterday, I observed a 4% performance improvement in an I/O bound read-write workload where the active working set does not fit in the buffer pool.

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          Rahul Raj
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          Rahul Raj
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          Rahul Raj

        Issue Links

          blocks

          Bug - A problem which impairs or prevents the functions of the product. MDEV-37115 Reverse index scan incurs unnecessary overhead

          • Critical - Crashes, loss of data, severe memory leak.
          • Stalled
          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-37753 lock_sec_rec_some_has_impl() unnecessarily fetches history and a freed BLOB

          • Major - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. MDEV-34431 More fine grained control of spin loops could be useful

          • Critical - Crashes, loss of data, severe memory leak.
          • Stalled

          Activity

            People

              marko Marko Mäkelä
              marko Marko Mäkelä
              Marko Mäkelä Marko Mäkelä
              Thirunarayanan Balathandayuthapani Thirunarayanan Balathandayuthapani
              Saahil Alam Saahil Alam
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                Created:
                Updated:
                Resolved: