Benefits for LWN subscribersThe primary benefit from subscribing to LWN is helping to keep us publishing, but, beyond that, subscribers get immediate access to all site content and access to a number of extra site features. Please sign up today! One year ago, the io_uring subsystem did not exist in the mainline kernel; it showed up in the 5.1 release in May 2019. At its core, io_uring is a mechani