show databases;
Database
information_schema
mtr
mysql
performance_schema
test
select count(*) from performance_schema.PERFORMANCE_TIMERS;
count(*)
5
select count(*) from performance_schema.SETUP_CONSUMERS;
count(*)
8
select count(*) > 0 from performance_schema.SETUP_INSTRUMENTS;
count(*) > 0
0
select count(*) from performance_schema.SETUP_TIMERS;
count(*)
1
select * from performance_schema.COND_INSTANCES;
select * from performance_schema.EVENTS_WAITS_CURRENT;
select * from performance_schema.EVENTS_WAITS_HISTORY;
select * from performance_schema.EVENTS_WAITS_HISTORY_LONG;
select * from performance_schema.EVENTS_WAITS_SUMMARY_BY_INSTANCE;
select * from performance_schema.EVENTS_WAITS_SUMMARY_BY_THREAD_BY_EVENT_NAME;
select * from performance_schema.EVENTS_WAITS_SUMMARY_GLOBAL_BY_EVENT_NAME;
select * from performance_schema.FILE_INSTANCES;
select * from performance_schema.FILE_SUMMARY_BY_EVENT_NAME;
select * from performance_schema.FILE_SUMMARY_BY_INSTANCE;
select * from performance_schema.MUTEX_INSTANCES;
select * from performance_schema.PERFORMANCE_TIMERS;
select * from performance_schema.RWLOCK_INSTANCES;
select * from performance_schema.SETUP_CONSUMERS;
select * from performance_schema.SETUP_INSTRUMENTS;
select * from performance_schema.SETUP_TIMERS;
select * from performance_schema.THREADS;
show variables like "performance_schema%";
Variable_name	Value
performance_schema	OFF
performance_schema_events_waits_history_long_size	10000
performance_schema_events_waits_history_size	10
performance_schema_max_cond_classes	80
performance_schema_max_cond_instances	1000
performance_schema_max_file_classes	50
performance_schema_max_file_handles	32768
performance_schema_max_file_instances	10000
performance_schema_max_mutex_classes	200
performance_schema_max_mutex_instances	1000
performance_schema_max_rwlock_classes	20
performance_schema_max_rwlock_instances	1000
performance_schema_max_table_handles	100000
performance_schema_max_table_instances	50000
performance_schema_max_thread_classes	50
performance_schema_max_thread_instances	1000
show engine PERFORMANCE_SCHEMA status;
show status like "performance_schema%";
show status like "performance_schema%";
Variable_name	Value
Performance_schema_cond_classes_lost	0
Performance_schema_cond_instances_lost	0
Performance_schema_file_classes_lost	0
Performance_schema_file_handles_lost	0
Performance_schema_file_instances_lost	0
Performance_schema_locker_lost	0
Performance_schema_mutex_classes_lost	0
Performance_schema_mutex_instances_lost	0
Performance_schema_rwlock_classes_lost	0
Performance_schema_rwlock_instances_lost	0
Performance_schema_table_handles_lost	0
Performance_schema_table_instances_lost	0
Performance_schema_thread_classes_lost	0
Performance_schema_thread_instances_lost	0