MySQL Enterprise Thread Pool MySQL Enterprise Thread Pool comprises these elements: •A plugin library file implements a plugin for the thread pool code as well as several associated monitoring tables that provide information about thread pool operation: •As of MySQL 8.0.14, the monitoring tables are Performance Schema tables; see Section 27.12.16, “Performance Schema Thread Pool Tables” . •Prior to MySQL 8.0.14, the monitoring tables are  INFORMATION_SCHEMA  tables; see Section 26.5, “INFORMATION_SCHEMA Thread Pool Tables” . The  INFORMATION_SCHEMA  tables now are deprecated; expect them to be removed in a future version of MySQL. Applications should transition away from the  INFORMATION_SCHEMA  tables to the Performance Schema tables. For example, if an application uses this query: The application should use this query instead: SELECT * FROM INFORMATION_SCHEMA.TP_THREAD_STATE; SELECT * FROM performance_schema.tp_thread_state; If you do not load all the monitoring tables, some or all MySQL Enterprise Monitor thread pool graphs may be empty. Note For a detailed description of how the thread pool works, see Section 5.6.3.3, “Thread Pool Operation” . •Several system variables are related to the thread pool. The  thread_handling  system variable has a value of  loaded-dynamically  when the server successfully loads the thread pool plugin. The other related system variables are implemented by the thread pool plugin and are not available unless it is enabled. For information about using these variables, see Section 5.6.3.3, “Thread Pool Operation” , and Section 5.6.3.4, “Thread Pool Tuning” . This section describes how to install MySQL Enterprise Thread Pool. For general information about installing plugins, see Section 5.6.1, “Installing and Uninstalling Plugins” . To be usable by the server, the plugin library file must be located in the MySQL plugin directory (the directory named by the  plugin_dir  system variable). If necessary, configure the plugin directory location by setting the value of  plugin_dir  at server startup. The plugin library file base name is  thread_pool . The file name suffix differs per platform (for example, .so  for Unix and Unix-like systems,  .dll  for Windows). •Thread Pool Installation as of MySQL 8.0.14 •Thread Pool Installation Prior to MySQL 8.0.14 •The Performance Schema has instruments that expose information about the thread pool and may be used to investigate operational performance. To identify them, use this query: SELECT * FROM performance_schema.setup_instruments WHERE NAME LIKE ’%thread_pool%’; For more information, see Chapter 27,  MySQL Performance Schema . 5.6.3.2 Thread Pool Installation 1080