How OpenAI Scaled Postgres to 800 Million Users (Step-by-Step)

Summary

OpenAI's technical article reveals their innovative approach to scaling Postgres for 800 million ChatGPT users, focusing on database infrastructure and replication strategies. The key technique involves maintaining a single primary write database while utilizing a fleet of approximately 50 read replicas, leveraging Postgres's write-ahead log for efficient data synchronization. This approach demonstrates a sophisticated method of horizontal scaling that allows systems to handle massive query loads by distributing read operations across multiple database instances while preserving a centralized write mechanism.