The following checklist was compiled in recent classes. Usage is simple: Check the listed things , and consider the actions on the right.
It's not commented, just use it as a cheat sheet. Check: Max_Used_Connections Action: Max_Connnections Check: Threads_% Action: Thread_Cache_Size Check: Opened_Tables, Open_Tables Action: Table_Cache Check: Created_Tmp_Tables, Created_Tmp_Disk_Tables Action: Tmp_Table_Size Check: Sort_% Action: Sort_Buffer Check: QCache_%, Com_Select Action: Query_Cache_% Check: Table_Locks_% Action: MyISAM -> InnoDB Check: Key_% Action: Key_Buffer_Size Check: SHOW INNODB STATUS Action: Innodb_Buffer_Pool_Size Check: PROCEDURE ANALYSE() Action: ALTER TABLE Check: (Slow) Query Log Action: EXPLAIN