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The Performance Schema is implemented as a storage engine, so you can see it listed in the output from the INFORMATION_SCHEMA.ENGINES  table or the SHOW ENGINES  statement: 

mysql> SELECT * FROM INFORMATION_SCHEMA.ENGINES WHERE ENGINE=’PERFORMANCE_SCHEMA’\G *************************** 1. row *************************** ENGINE: PERFORMANCE_SCHEMA SUPPORT: YES COMMENT: Performance Schema TRANSACTIONS: NO XA: NO SAVEPOINTS: NO mysql> SHOW ENGINES\G ... Engine: PERFORMANCE_SCHEMA Support: YES Comment: Performance Schema Transactions: NO XA: NO Savepoints: NO ... 

The PERFORMANCE_SCHEMA  storage engine operates on tables in the performance_schema  database. You can make performance_schema  the default database so that references to its tables need not be qualified with the database name: 

mysql> USE performance_schema; 

Performance Schema tables are stored in the performance_schema  database. Information about the structure of this database and its tables can be obtained, as for any other database, by selecting from the INFORMATION_SCHEMA  database or by using SHOW  statements. For example, use either of these statements to see what Performance Schema tables exist: 

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