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  1. Core Server
  2. SERVER-9754

Every write to journal costs additional seek to update file metadata

    • Type: Icon: Improvement Improvement
    • Resolution: Done
    • Priority: Icon: Major - P3 Major - P3
    • 2.4.6, 2.5.1
    • Affects Version/s: 2.4.3
    • Component/s: Performance
    • Environment:
      Windows 7 Professional x64 SP1
    • Fully Compatible

      Journal file is created with FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH attributes, but FILE_FLAG_WRITE_THROUGH is not needed here and even worse it flushes NTFS metadata on every write operation. Removing it doesn't affect durability (FILE_FLAG_NO_BUFFERING does it's job), but greatly improves performance and reduces disk load.

      You can read detailed explanation here http://dmitry-naumov.blogspot.ru/2013/05/mongodb-vs-ms-sql-how-to-write-to.html

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            Assignee:
            tad Tad Marshall
            Reporter:
            dnaumov Dmitry Naumov
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              Created:
              Updated:
              Resolved: