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https://dev.mysql.com/doc/refman/8.4/en/performance-schema-events-waits-current-table.html
The table stores one row per thread showing the current status of the thread's most recent monitored wait event, so there is no system variable for configuring the table size. Of the tables that contain wait event rows, events_waits_current is the ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-host-cache-table.html
The MySQL server maintains an in-memory host cache that contains client host name and IP address information and is used to avoid Domain Name System (DNS) lookups. The host_cache_size system variable controls the size of the host cache, as well as ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instrumentation-checking.html
It is always possible to determine what instruments the Performance Schema includes by checking the setup_instruments table. Changes to this code occur often, which also affects the set of instruments. It is not practical to list all the ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-keyring-component-status-table.html
The keyring_component_status table provides status information about the properties of the keyring component in use, if one is installed. The table is empty if no keyring component is installed (for example, if the keyring is not being used, or is ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-log-status-table.html
The log_status table provides information that enables an online backup tool to copy the required log files without locking those resources for the duration of the copy process. When the log_status table is queried, the server blocks logging and ...
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-memory-summary-tables.html
Operation counts help to understand or tune the overall pressure the server is putting on the memory allocator, which has an impact on performance. Allocating a single byte one million times is not the same as allocating one million bytes a single ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-ndb-sync-excluded-objects-table.html
This table provides information about NDB database objects which cannot be automatically synchronized between NDB Cluster's dictionary and the MySQL data dictionary. Example information about NDB database objects which cannot be synchronized with ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-ndb-sync-pending-objects-table.html
This table provides information about NDB database objects for which mismatches have been detected and which are waiting to be synchronized between the NDB dictionary and the MySQL data dictionary.
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-object-filtering.html
The setup_objects table controls whether the Performance Schema monitors particular table and stored program objects. The OBJECT_TYPE column indicates the type of object to which a row applies. TABLE filtering affects table I/O events ...