Postgres Deployment Data Volume not Matching DB?

I’m having an issue trying to understand why my health check for “checkdisk” on the VM returns critical with the following message:

checkDisk: 8.98 GB (91.9%!)(MISSING) free space on /data/ (235.04µs)\n[✓]

Is that saying that I have 8.98 GB free or that it’s all in use? If I look at the data size of the tables in my app, the biggest one is 50 mb and so I can’t possibly see how I’m taking up almost 9 gb?

(I’m trying to debug some db crashes here which led me down the path of investigating this failing health check)

The error I’m getting in my PG logs is:

FATAL: could not receive data from WAL stream: server closed the connection unexpectedly

and

The postmaster has commanded this server process to roll back the current transaction and exit, because another server process exited abnormally and possibly corrupted shared memory.

What’s odd is this is our staging deployment. Production is working fine…

This is a Phoenix Elixir application and this crash always coincides with all of my Oban workers crashing.