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Oracle Enterprise Manager for MySQL Database User's Guide  /  Configuration Metrics  /  Performance Schema Configuration Metrics

7.26 Performance Schema Configuration Metrics

Lists the Performance Schema configuration metrics and provides a brief description of each.

Table 7.26 Performance Schema Configuration Metrics

NameDescription
Accounts SizeThe number of rows in the accounts table.
Digests SizeThe maximum number of rows in the events_statements_summary_by_digest table.
EnabledThe value of this variable is ON or OFF to indicate whether the Performance Schema is enabled. By default, the value is OFF. At server startup, you can specify this variable with no value or a value of 1 to enable it, or with a value of 0 to disable it.
Error SizeThe number of instrumented server error codes. By default all errors are instrumented.
Events Stages History Long SizeThe number of rows in the events_stages_history_long table.
Events Stages History SizeThe number of rows in the events_stages_history table.
Events Statements History Long SizeThe number of rows in the events_statements_history_long table.
Events Statements History SizeThe number of rows in the events_statements_history table.
Events Transactions History Long SizeThe number of rows in the events_transactions_history_long table.
Events Transactions History SizeThe number of rows per thread in the events_transactions_history table.
Events Waits History Long SizeThe number of rows in the events_waits_history_long table.
Events Waits History SizeThe number of rows per thread in the events_waits_history table.
Hosts SizeThe number of rows in the hosts table.
Max Cond ClassesThe maximum number of condition instruments.
Max Cond InstancesThe maximum number of instrumented condition objects.
Max Digest LengthThe maximum number of bytes available for computing statement digests.
Max Digest Sample AgeThe query resample age (in seconds) for the events_statements_summary_by_digest table. Default value is 60 seconds.
Max File ClassesThe maximum number of file instruments.
Max File HandlesThe maximum number of opened file objects. The value of performance_schema_max_file_handles should be greater than the value of open_files_limit: open_files_limit affects the maximum number of open file handles the server can support and performance_schema_max_file_handles affects how many of these file handles can be instrumented.
Max File InstancesThe maximum number of instrumented file objects.
Max Index StatThe maximum number of indexes for which the Performance Schema maintains statistics.
Max Memory ClassesThe maximum number of memory instruments.
Max Metadata LocksThe maximum number of metadata lock instruments.
Max Mutex ClassesThe maximum number of mutex instruments.
Max Mutex InstancesThe maximum number of instrumented mutex objects.
Max Prepared Statements InstancesThe maximum number of rows in the prepared_statements_instances table.
Max Program InstancesThe maximum number of stored programs for which the Performance Schema maintains statistics.
Max Rwlock ClassesThe maximum number of rwlock instruments.
Max Rwlock InstancesThe maximum number of instrumented rwlock objects.
Max Socket ClassesThe maximum number of socket instruments.
Max Socket InstancesThe maximum number of instrumented socket objects.
Max SQL Text LengthThe maximum number of bytes used to store SQL statements in the SQL_TEXT column of the events_statements_current, events_statements_history, and events_statements_history_long statement event tables.
Max Stage ClassesThe maximum number of stage instruments.
Max Statement ClassesThe maximum number of statement instruments. The default value is calculated at server build time based on the number of commands in the client/server protocol and the number of SQL statement types supported by the server.
Max Statement StackThe maximum depth of nested stored program calls for which the Performance Schema maintains statistics.
Max Table HandlesThe maximum number of opened table objects.
Max Table InstancesThe maximum number of instrumented table objects.
Max Table Lock StatThe maximum number of tables for which the Performance Schema maintains lock statistics.
Max Thread ClassesThe maximum number of thread instruments.
Max Thread InstancesThe maximum number of instrumented thread objects. The max_connections and max_delayed_threads system variables affect how many threads are run in the server. performance_schema_max_thread_instances affects how many of these running threads can be instrumented. If you increase max_connections or max_delayed_threads, consider increasing performance_schema_max_thread_instances so that performance_schema_max_thread_instances is greater than the sum of max_connections and max_delayed_threads.
Session Connect Attrs SizeThe amount of preallocated memory per thread used to hold connection attribute strings.
Setup Actors SizeThe number of rows in the setup_actors table.
Setup Objects SizeThe number of rows in the setup_objects table.
Users SizeThe number of rows in the users table.