- The service mentioned (now called https://webapp.io ) eventually made it into YC (S20) and still uses postgres as its pub/sub implementation, doing hundreds of thousands of messages per day. The postgres instance now runs on 32 cores and 128gb of memory and has scaled well.
- We bolstered Postgres's PUBLISH with Redis pub/sub for high traffic code paths, but it's been nice having ACID guarantees as the default for less popular paths (e.g., webhook handling)
- This pattern only ever caused one operational incident, where a transaction held a lock which caused the notification queue to start growing, and eventually (silently) stop sending messages, starting postgres with statement_timeout=(a few days) was enough to solve this
Previous discussion: https://news.ycombinator.com/item?id=21484215
Happy to answer any questions!
> The postgres instance now runs on 32 cores and 128gb of memory and has scaled well.
Am I the only one?
That said, it's been running for upwards of 4 years and accumulated an insane number of temperature readings inside and above heating vents (heat source is heat pump)
SELECT count() as count FROM temperatures : msg : Object { _msgid: "421b3777.908118", topic: "SELECT count() as count FROM …", payload: 23278637 }
Ok, I need therapy for my data hoarding - 23 million temp samples is not a good sign :-)
My experience with SQLite is that it can take you a long ways before needing to look elsewhere.