# free -m # ps aux | egrep 'mysqld|VSZ' # vmstat 1 # iostat -xk 1 # mpstat -P ALL 1 mysql> SHOW GLOBAL STATUS LIKE 'Open%tables'; mysql> SHOW GLOBAL VARIABLES WHERE variable_name = 'max_connections' OR variable_name = 'table_open_cache'; mysql> SELECT COUNT(*) FROM information_schema.tables; mysql> SELECT * FROM employee WHERE last = 'Mueller'; mysql> EXPLAIN SELECT * FROM employee WHERE last = 'Mueller'; mysql> ALTER TABLE employee ADD INDEX (last); mysql> EXPLAIN SELECT * FROM employee WHERE last = 'Mueller'; mysql> SET GLOBAL slow_query_log = 1; mysql> SET GLOBAL long_query_time = 0.200; mysql> SHOW GLOBAL VARIABLES LIKE 'slow%file';