https://dev.mysql.com/performance-schema-build-configuration.html
Because the Performance Schema is configured into the server at build time, a row for PERFORMANCE_SCHEMA appears in the output from SHOW ENGINES. It is possible to exclude certain parts of the Performance Schema instrumentation. For example, to ...
https://dev.mysql.com/performance-schema-connection-tables.html
Suppose that clients named user1 and user2 each connect one time from hosta and hostb. When a client connects to the MySQL server, it does so under a particular user name and from a particular host. They differ in that, for grant tables, the host ...
https://dev.mysql.com/performance-schema-consumer-filtering.html
If you disable a consumer, the server does not spend time maintaining destinations for that consumer. To enable or disable a consumer, set its ENABLED value to YES or NO. For example, if you do not care about historical event information, disable ...
https://dev.mysql.com/performance-schema-ndb-cluster-tables.html
If synchronization of the object fails due to a temporary error, it is picked up and added back to the queue (and to this table) the next time NDB performs mismatch detection; if the attempts fails due a permanent error, the object is added to the ... Beginning with NDB 8.0.16, automatic synchronization in NDB attempts to detect and synchronize automatically all mismatches in metadata between the NDB Cluster's internal dictionary and the MySQL Server's ...
https://dev.mysql.com/performance-schema-obtaining-parent-events.html
If a statement that executed a long time ago took a lock but is in a still-open transaction, it might not be possible to find the statement, but it is possible to find the transaction. Rows of this table have a THREAD_ID column indicating the thread ...
https://dev.mysql.com/performance-schema-runtime-configuration.html
Specific Performance Schema features can be enabled at runtime to control which types of event collection occur. If there are Performance Schema configuration changes that must be made at runtime using SQL statements and you would like these ...If ...
https://dev.mysql.com/performance-schema-status-monitoring.html
For example, if a mutex is instrumented in the server source but the server cannot allocate memory for the instrumentation at runtime, it increments Performance_schema_mutex_classes_lost. Other mutexes have an instance per connection, or per page in ...Names for these variables have several forms: Performance_schema_xxx_classes_lost indicates how many instruments of type xxx could not be ...
https://dev.mysql.com/performance-schema-summary-tables.html
Summary tables provide aggregated information for terminated events over time. That might be useful, for example, after you have made a runtime configuration change. The tables in this group summarize event data in different ways. Tables that ...
https://dev.mysql.com/plugin-api-characteristics.html
If the API changes over time, the version numbers will change, but a server can examine a given plugin library's version information to determine whether it supports the plugins in the library. A plugin library must be installed in a specific ...
https://dev.mysql.com/plugin-api-components.html
Command-line options and system variables: The --plugin-load option enables plugins to be loaded at server startup time. SQL statements: INSTALL PLUGIN registers a plugin in the mysql.plugin table and loads the plugin code. UNINSTALL PLUGIN ...