Skip navigation links
5.3.2 Changes in MySQL 5.4.2 (01 September 2009) »
Section Navigation      [Toggle]

5.3.1. Changes in MySQL 5.4.3 (06 October 2009)

Functionality added or changed:

  • Incompatible Change: If you upgrade to MySQL 5.4.3 from an earlier 5.4 release, the server may fail to start due to changes in the default values of innodb_log_files_in_group and innodb_log_file_size, which differ from those in earlier 5.4 releases. You should discard the old InnoDB log files and let MySQL 5.4.3 create new ones. It is necessary to shut down your current server cleanly so that no outstanding transaction information remains in the log. The procedure to use depends on the value of innodb_fast_shutdown used in your current server:

    • If innodb_fast_shutdown is not set to 2: Stop your current MySQL server and make sure that it shuts down without errors (to ensure that there is no information for outstanding transactions in the log). Copy the old log files into a safe place in case something went wrong during the shutdown and you need them to recover the tablespace. Delete the old log files and edit my.cnf if necessary to specify the desired log file configuration. Then upgrade to MySQL 5.4.3 and start the new server. mysqld sees that no InnoDB log files exist at startup and creates new ones.

    • If innodb_fast_shutdown is set to 2: Shut down your current server, set innodb_fast_shutdown to 1, and restart the server. The server should be allowed to recover. Then you should shut down the server again and follow the procedure described in the preceding item to change InnoDB log file size. Set innodb_fast_shutdown back to 2 and start the MySQL 5.4.3 server.

  • Incompatible Change: The following list indicates InnoDB configuration changes in MySQL 5.4.3, compared to previous versions of MySQL 5.4. For a description of cumulative changes in MySQL 5.4 compared to MySQL 5.1, see MySQL 4.1 in a Nutshell.

    The default value of these system variables was changed:

    Variable Change in default value
    innodb_autoextend_increment From 64MB to 8MB
    innodb_buffer_pool_size From 1GB to 128MB
    innodb_log_buffer_size From 16MB to 8MB
    innodb_log_file_size From 128MB to 5MB
    innodb_log_files_in_group From 3 to 2
    innodb_read_io_threads From 8 to 4
    innodb_write_io_threads From 8 to 4

    These default value changes in most cases revert changes made in earlier MySQL 5.4 releases. The result is that the defaults are more similar to those in MySQL 5.1.