Documentation Home
MySQL 8.0 Reference Manual
Related Documentation Download this Manual
PDF (US Ltr) - 46.7Mb
PDF (A4) - 46.8Mb
PDF (RPM) - 42.2Mb
HTML Download (TGZ) - 10.8Mb
HTML Download (Zip) - 10.8Mb
HTML Download (RPM) - 9.3Mb
Man Pages (TGZ) - 224.5Kb
Man Pages (Zip) - 329.9Kb
Info (Gzip) - 4.2Mb
Info (Zip) - 4.2Mb
Excerpts from this Manual

MySQL 8.0 Reference Manual  /  MySQL Performance Schema  /  Performance Schema Status Variables

26.16 Performance Schema Status Variables

The Performance Schema implements several status variables that provide information about instrumentation that could not be loaded or created due to memory constraints:

mysql> SHOW STATUS LIKE 'perf%';
+-------------------------------------------+-------+
| Variable_name                             | Value |
+-------------------------------------------+-------+
| Performance_schema_accounts_lost          | 0     |
| 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_hosts_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_socket_classes_lost    | 0     |
| Performance_schema_socket_instances_lost  | 0     |
| Performance_schema_stage_classes_lost     | 0     |
| Performance_schema_statement_classes_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     |
| Performance_schema_users_lost             | 0     |
+-------------------------------------------+-------+

For information on using these variables to check Performance Schema status, see Section 26.7, “Performance Schema Status Monitoring”.

Performance Schema status variables have the following meanings: