Alert rules

This page contains a markdown version of the alert rules described in the mysql-operator repository. The following file(s) are the source of truth:

• alert_rules/prometheus/metrics_alert_rules.yaml

This documentation describes the latest alert rule expressions. See the YAML file(s) on listed above if you require an older version.

MySQLExporter

Alert	Severity	Notes
MySQLDown		MySQL instance is down.
MySQLTooManyConnections(>90%)		MySQL instance is using > 90% of max_connections. Consider checking the client application responsible for generating those additional connections.
MySQLHighThreadsRunning		MySQL instance is actively using > 80% of max_connections. Consider reviewing the value of the max-connections config parameter or allocate more resources to your database server.
MySQLHighPreparedStatementsUtilization(>80%)		MySQL instance is using > 80% of max_prepared_stmt_count. Too many prepared statements might consume a lot of memory.
MySQLSlowQueries		MySQL instance has a slow query. Consider optimizing the query by reviewing its execution plan, then rewrite the query and add any relevant indexes.
MySQLInnoDBLogWaits		MySQL instance has long InnoDB log waits. MySQL InnoDB log writes might be stalling. Check I/O activity on your nodes to find the responsible process or query. Consider using iotop and the performance_schema.
MySQLRestarted		MySQL instance restarted. MySQL restarted less than one minute ago. If the restart was unplanned or frequent, check Loki logs (e.g. error.log).