In Linux, there are two interfaces for efficient asynchronous disk I/O: traditional AIO (libaio) and the newer io_uring (liburing). It is well known that io_uring outperforms AIO. A number of papers demonstrate this, and kernel developers often mention that io_uring performance improved significantly after the initial releases. However, it is surprisingly hard to find concrete numbers showing how this performance evolved across kernel versions. Most benchmarks compare APIs on a single kernel, le...