POSTGRES POSTMASTER DOES NOT SCALE

Summary from the TLDR Dev newsletter

Recall.ai, a company recording millions of meetings weekly, encountered perplexing 10-15 second connection delays to its Postgres database during peak loads. Investigations revealed the bottleneck was in Postgres's single-threaded "postmaster" process, which is responsible for spawning new connections and background workers. High rates of new connections and background worker churn during synchronized meeting “starts” saturated this core process, so the company implemented jitter in its EC2 connection bursts and removed parallel query spikes.