Level: Intermediate
PostgreSQL’s LISTEN/NOTIFY sounds awesome: a built-in, lightweight message bus without the infrastructure headaches. But hidden inside this elegant feature is a mechanic that can silently kill your concurrency.
In this lightning talk, I will expose the "global exclusive lock" mechanism used to serialize notifications that most developers miss until production hits peak traffic. I’ll share a quick real story of how a simple trigger could bring our database to a crawl, and I’ll leave you with the architecture pattern you need to use NOTIFY safely at scale.