MySQL 8.3 Release Notes
该 setup_meters 表列出了已注册的计量器：
mysql> select * from performance_schema.setup_meters;
+------------------------+-----------+---------+-------------------------------------------+
| NAME | FREQUENCY | ENABLED | DESCRIPTION |
+------------------------+-----------+---------+-------------------------------------------+
| mysql.inno | 10 | YES | MySql InnoDB metrics |
| mysql.inno.buffer_pool | 10 | YES | MySql InnoDB buffer pool metrics |
| mysql.inno.data | 10 | YES | MySql InnoDB data metrics |
| mysql.x | 10 | YES | MySql X plugin metrics |
| mysql.x.stmt | 10 | YES | MySql X plugin statement statistics |
| mysql.stats | 10 | YES | MySql core metrics |
| mysql.stats.com | 10 | YES | MySql command stats |
| mysql.stats.connection | 10 | YES | MySql connection stats |
| mysql.stats.handler | 10 | YES | MySql handler stats |
| mysql.stats.ssl | 10 | YES | MySql TLS related stats |
| mysql.myisam | 10 | YES | MySql MyISAM storage engine stats |
| mysql.perf_schema | 10 | YES | MySql performance_schema lost instruments |
+------------------------+-----------+---------+-------------------------------------------+-
名称：计量器的名称。 -
频率：以秒为单位的指标导出频率。默认每 10 秒导出一次。此值可以对已注册的计量器进行编辑。 -
启用：是否启用计量器。值为 YES 或 NO。禁用的计量器不导出指标。此列可以修改 -
描述：计量器的描述字符串。
频率 和 启用 可以编辑。