The instrument name. Thread instruments begin with thread  (for example, thread/sql/ parser_service  or thread/performance_schema/setup ). 

• ENABLED 

Whether the instrument is enabled. The value is YES  or NO . This column can be modified, although setting ENABLED  has no effect for threads that are already running. 

For background threads, setting the ENABLED  value controls whether INSTRUMENTED  is set to YES  or NO  for threads that are subsequently created for this instrument and listed in the threads  table. For foreground threads, this column has no effect; the setup_actors  table takes precedence. 

• HISTORY 

Whether to log historical events for the instrument. The value is YES  or NO . This column can be modified, although setting HISTORY  has no effect for threads that are already running. 

For background threads, setting the HISTORY  value controls whether HISTORY  is set to YES  or NO  for threads that are subsequently created for this instrument and listed in the threads  table. For foreground threads, this column has no effect; the setup_actors  table takes precedence. 

• PROPERTIES 

The instrument properties. This column uses the SET  data type, so multiple flags from the following list can be set per instrument: 

• singleton : The instrument has a single instance. For example, there is only one thread for the thread/sql/main  instrument. 

• user : The instrument is directly related to user workload (as opposed to system workload). For example, threads such as thread/sql/one_connection  executing a user session have the user property to differentiate them from system threads. 

• VOLATILITY 

The instrument volatility. This column has the same meaning as in the setup_instruments  table. See Section 27.12.2.3, “The setup_instruments Table” . 

• DOCUMENTATION 

A string describing the instrument purpose. The value is NULL  if no description is available. 

## 27.12.2.6 The setup_timers Table 

## 27.12.3 Performance Schema Instance Tables 

The setup_threads  table has these indexes: 

•Primary key on ( NAME ) 

TRUNCATE TABLE  is not permitted for the setup_threads  table. 

This table was removed in MySQL 8.0.4. 

Instance tables document what types of objects are instrumented. They provide event names and explanatory notes or status information: 

