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https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instrument-filtering.html
Some of these queries use the LIKE operator and a pattern match instrument names. The setup_instruments table lists the available instruments: mysql> SELECT NAME, ENABLED, TIMED FROM performance_schema.setup_instruments; ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instrument-naming.html
An instrument name consists of a sequence of elements separated by '/' characters. Example names: wait/io/file/myisam/log wait/io/file/mysys/charset wait/lock/table/sql/handler wait/synch/cond/mysys/COND_alarm ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-log-status-table.html
When the log_status table is queried, the server blocks logging and related administrative changes for just long enough to populate the table, then releases the resources. The log_status table provides information that enables an online backup tool ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-memory-model.html
Memory used depends on the load actually seen, not the load estimated or explicitly configured for. As the Performance Schema collects data, memory is allocated in the corresponding buffer. The buffer size is unbounded, and may grow with the load.
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-prepared-statements-instances-table.html
The Performance Schema provides instrumentation for prepared statements, for which there are two protocols: The binary protocol. This is accessed through the MySQL C API and maps onto underlying server commands as shown in the following table. C ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-rwlock-instances-table.html
The rwlock_instances table lists all the rwlock (read write lock) instances seen by the Performance Schema while the server executes. An rwlock is a synchronization mechanism used in the code to enforce that threads at a given time can have access ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-setup-metrics-table.html
row *************************** NAME: slow_queries METER: mysql.stats METRIC_TYPE: ASYNC COUNTER NUM_TYPE: INTEGER UNIT: DESCRIPTION: The number of queries that have taken more than long_query_time seconds (Slow_queries) ... The setup_metrics table ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-system-variables.html
This implementation queries active thread data from the Performance Schema rather than the thread manager and does not require a mutex. The Performance Schema automatically sizes the values of several of its parameters at server startup if they are ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-timing.html
Events are collected by means of instrumentation added to the server source code. Instruments time events, which is how the Performance Schema provides an idea of how long events take. It is also possible to configure instruments not to collect ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-tp-thread-group-state-table.html
That is, these two queries are equivalent: SELECT TP_GROUP_ID, MAX_THREAD_IDS_IN_GROUP FROM tp_thread_group_state; SELECT TP_GROUP_ID, MAX(TP_THREAD_NUMBER) FROM tp_thread_state GROUP BY TP_GROUP_ID; EFFECTIVE_MAX_TRANSACTIONS_LIMIT The effective ...