Asynchronous IO lands in Postgres 18 (and it’s worth the hype)

Postgres 18 just dropped with a handful of neat toys—think UUIDv7, an over-explain module, composite-index skip scans—and the crown jewel: true async IO. In the latest Backend Engineering Show, Hussein breaks down sync vs async calls, revisits Postgres 17’s IO model, and walks you through the new worker and io_uring modes (plus the fallback sync path) that finally unblock nonblocking disk operations.

He also teases upcoming polish—backend-writer support, direct IO tweaks, and more—so you can expect async IO to keep cooking in future releases. If you’ve ever wondered how Postgres tackles OS-level IO under the hood, this deep dive has all the timestamps, tips, and follow-along courses you need to level up your backend game.

Watch on YouTube