How io_uring Overtook libaio: Performance Across Linux Kernels — and an Unexpected IOMMU Trap

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, leaving th