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  1. MariaDB Server
  2. MDEV-5766

my_atomic_load does memory writes

        Details

        • Type: Bug
        • Status: Closed
        • Priority: Minor
        • Resolution: Fixed
        • Affects Version/s: 10.0.8
        • Fix Version/s: 10.0.10
        • Component/s: None
        • Labels:
          None

          Description

          Any number of threads can read from a shared memory location simultaneously whereas at most one thread can write to a shared memory location at the same time.

          Atomic load shouldn't sacrifice scalability in this way. Use __atomic_load_n() whenever it is available for atomic loads.

          Currently it doesn't seem to cause any problems because atomic loads are rarely used during SQL statement execution. OTOH performance schema seem to be using atomic loads heavily.

          More information: http://svoj-db.blogspot.ru/2014/02/mariadb-scalability-atomic-load.html

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                svoj Sergey Vojtovich added a comment -

                Sergei, please review fix for this bug.

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                svoj Sergey Vojtovich added a comment - Sergei, please review fix for this bug.
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                svoj Sergey Vojtovich added a comment -

                Fixed in 10.0.10, revno: 4045, revision-id: svoj@mariadb.org-20140307074306-blf3begv8ee0tb5j

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                svoj Sergey Vojtovich added a comment - Fixed in 10.0.10, revno: 4045, revision-id: svoj@mariadb.org-20140307074306-blf3begv8ee0tb5j

                  People

                  • Assignee:
                    svoj Sergey Vojtovich
                    Reporter:
                    svoj Sergey Vojtovich
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                    • Created:
                      Updated:
                      Resolved: