content_image/854290.jpg content_image/854299.jpg content_image/854300.jpg
<img src='content_image/854290.jpg'>

This variable is only relevant if you have numerous InnoDB  tablespaces. It specifies the maximum number of .ibd  files that MySQL can keep open at one time. The minimum value is 10. The default value is 300 if innodb_file_per_table  is not enabled, and the higher of 300 and table_open_cache  otherwise. 

The file descriptors used for .ibd  files are for InnoDB  tables only. They are independent of those specified by the open_files_limit  system variable, and do not affect the operation of the table cache. For general I/O tuning advice, see Section 8.5.8, “Optimizing InnoDB Disk I/O” . 

Prior to MySQL 8.0.24, temporary tablespaces were counted as open files, which could cause the innodb_open_files  limit to be exceeded, preventing other files from being opened. As of MySQL 8.0.24, temporary tablespaces are not counted as open files. 

• innodb_optimize_fulltext_only 

<img src='content_image/854299.jpg'>

Changes the way OPTIMIZE TABLE  operates on InnoDB  tables. Intended to be enabled temporarily, during maintenance operations for InnoDB  tables with FULLTEXT  indexes. 

By default, OPTIMIZE TABLE  reorganizes data in the clustered index of the table. When this option is enabled, OPTIMIZE TABLE  skips the reorganization of table data, and instead processes newly added, deleted, and updated token data for InnoDB FULLTEXT  indexes. For more information, see Optimizing InnoDB Full-Text Indexes. 

• innodb_page_cleaners 

<img src='content_image/854300.jpg'>

