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From:Michael Widenius Date:April 27 1999 12:04am
Subject:about --skip-locking
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>>>>> "Albert" == Albert Braun <albert_b@stripped> writes:

Albert> Hi,
Albert> The MySQL manual says: The --skip-locking option disables file locking
Albert> between SQL requests. This gives greater speed but has the following
Albert> consequences: You MUST flush all tables with mysqladmin flush-tables
Albert> before you try to check or repair tables with isamchk. (isamchk -d
Albert> tbl_name is always allowed, since that simply displays table
Albert> information.) You can't run two MySQL servers on the same data files, if
Albert> both are going to update the same tables.

Albert> But I still have a question: When running just *one* MySQL server, does
Albert> --skip-locking affect the table lock associated with updates and
Albert> inserts? In other words, when running a single mysqld process, can I
Albert> expect --skip-locking to provide any performance improvement on
Albert> concurrent updates/inserts to the same table?

--skip-locking will always improve performance.

If you are not using --skip-locking, MySQL will make a system lock for 
each table (with fcntl()) before accessing it.   (and fcntl() may be
VERY slow!)

about --skip-lockingAlbert Braun26 Apr
  • about --skip-lockingMichael Widenius27 Apr