Not running a relay yet, though. What stack are you using? I think you talked about Golang elsewhere? (I use go-nostr.)
https://sps.bio/stats I mostly persist text notes, and have some legacy Twitter and Hacker News posts indexed. 600GB NVMe SSD so far.
Discussion
Running strfry for the relay with a plugin for it in go. I'm also building out a stack to create and manage relays GitHub.com/relaytools