How do I get TotalStorageSpace or UsedStorageSpace metric from AWS RDS?

Question

I see that AWS RDS provides a FreeStorageSpace metric for monitoring disk usage. Now I am trying to create a generic pre-emptive alert for all my R

Answer 1

According to the doc FreeStorageSpace is the only StorageSpace metrics you can get.

I can only assume that their logic is that you know what is your total space and having the FreeStorageSpace value you can also calculate how much is used.