Server System Variables Default Value OFF Whether to write a core file if the server unexpectedly exits. This variable is set by the  --core-file option. • create_admin_listener_thread Command-Line Format --create-admin-listener-thread[={OFF| ON}] Introduced 8.0.14 System Variable create_admin_listener_thread Scope Global Dynamic No SET_VAR  Hint Applies No Type Boolean Default Value OFF Whether to use a dedicated listening thread for client connections on the administrative network interface (see Section 5.1.12.1, “Connection Interfaces” ). The default is  OFF ; that is, the manager thread for ordinary connections on the main interface also handles connections for the administrative interface. Depending on factors such as platform type and workload, you may find one setting for this variable yields better performance than the other setting. Setting  create_admin_listener_thread  has no effect if  admin_address  is not specified because in that case the server maintains no administrative network interface. • cte_max_recursion_depth Command-Line Format --cte-max-recursion-depth=# System Variable cte_max_recursion_depth Scope Global, Session Dynamic Yes SET_VAR  Hint Applies No Type Integer Default Value 1000 Minimum Value 0 Maximum Value 4294967295 The common table expression (CTE) maximum recursion depth. The server terminates execution of any CTE that recurses more levels than the value of this variable. For more information, see Limiting Common Table Expression Recursion. • datadir Command-Line Format --datadir=dir_name System Variable datadir Scope Global 785