Use Health Monitor and HeatWave Service metric, DbVolumeUtilization, to track storage space utilization for a DB system and to warn you if there is a shortage of space on the disk.

You can check the amount of disk space that is currently in use by these methods:

• Health Monitor: MySQL Health Monitor automatically sends warning messages if the free disk space for a DB system falls below 20%, 10%, and 5% of the available storage. If the DB system spends too long with too little free disk space or falls below its critical threshold, Health Monitor sets SUPER_READ_ONLY and OFFLINE_MODE system variables. When the disk space improves, the Health Monitor clears the system variables. See Health Monitor.
• DbVolumeUtilization metric: You can use the HeatWave Service metric DbVolumeUtilization in the oci_mysql_database namespace to create a query that actively monitors the disk space utilization for the DB system. Then, you can create an alarm to get notifications when the DbVolumeUtilization metric meets the alarm-specified triggers. The alarm sends a notification when disk space utilization reaches the level you set. For more information, see Using Metrics to Create Alarms.