MySQL 5.7 Release Notes
        
Given a connection ID, enables Performance Schema instrumentation for the thread. Produces a result set indicating how many threads were enabled. Already enabled threads do not count.
- in_connection_id BIGINT: The connection ID. This is a value of the type given in the- PROCESSLIST_IDcolumn of the Performance Schema- threadstable or the- Idcolumn of- SHOW PROCESSLISToutput.
Enable a specific connection by its connection ID:
mysql> CALL sys.ps_setup_enable_thread(225);
+------------------+
| summary          |
+------------------+
| Enabled 1 thread |
+------------------+Enable the current connection:
mysql> CALL sys.ps_setup_enable_thread(CONNECTION_ID());
+------------------+
| summary          |
+------------------+
| Enabled 1 thread |
+------------------+