17.14 InnoDB Startup Options and System Variables

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MySQL 8.4 Reference Manual Including MySQL NDB Cluster 8.4

17.14 InnoDB Startup Options and System Variables

• InnoDB Startup Options

• InnoDB System Variables

• System variables that are true or false can be enabled at server startup by naming them, or disabled by using a --skip- prefix. For example, to enable or disable the InnoDB adaptive hash index, you can use --innodb-adaptive-hash-index or --skip-innodb-adaptive-hash-index on the command line, or innodb_adaptive_hash_index or skip_innodb_adaptive_hash_index in an option file.

• Some variable descriptions refer to “enabling” or “disabling” a variable. These variables can be enabled with the SET statement by setting them to ON or 1, or disabled by setting them to OFF or 0. Boolean variables can be set at startup to the values ON, TRUE, OFF, and FALSE (not case-sensitive), as well as 1 and 0. See Section 6.2.2.4, “Program Option Modifiers”.
• System variables that take a numeric value can be specified as --var_name=value on the command line or as var_name=value in option files.
• Many system variables can be changed at runtime (see Section 7.1.9.2, “Dynamic System Variables”).
• For information about GLOBAL and SESSION variable scope modifiers, refer to the SET statement documentation.
• Certain options control the locations and layout of the InnoDB data files. Section 17.8.1, “InnoDB Startup Configuration” explains how to use these options.
• Some options, which you might not use initially, help tune InnoDB performance characteristics based on machine capacity and database workload.
• For more information on specifying options and system variables, see Section 6.2.2, “Specifying Program Options”.

Table 17.23 InnoDB Option and Variable Reference

InnoDB Startup Options

• --innodb-dedicated-server

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