So we run on RDS, and we clearly used up all of our provisioned storage. However, I am baffled, and while I am emailing our AWS support, I wondered if this list might point me in some direction too.
Our provisioned storage was 15TB. The size of our database -- shown in pg_database -- is only 6TB. What in the world could be using that remaining space? I am at a loss, that's a _ton_ of space being used up. Is it some temporary allocation during script execution (seems ginormous, impossible)? It it some WAL log thing?
A fairly common cause of this is orphan replication slots so WAL files are retained. Check
to see if there is an inactive slot that may be preventing the files to be removed.