We're currently experiencing an issue with our RDS instance, where the cloudwatch dashboard is only reporting CPU for the instance (no metrics for database connections, ReadIOPS, WriteIOPS, etc).
We're also seeing a large number of errors in the logs like:
2021-08-02 15:28:26 UTC::@:[74500]:LOG: could not open log file "/rdsdbdata/log/error/postgresql.log.2021-08-02-15": Too many open files in system
This is a db.r4.8xlarge postgresql instance. I'm not quite sure why cloudwatch isn't showing any metrics for this, but I have a feeling it's likely related to the open files issue. This is relatively high priority for us, so any help is appreciated.