Release 3.5.0 — Linux io_uring Backend

Release 3.5.0 — Linux io_uring Backend

Overview

This release introduces a new io_uring-based backend for Linux, providing an alternative to the existing epoll engine.
It integrates directly into Uvent’s coroutine I/O pipeline and keeps the same high-level API, adding a lower-overhead I/O submission path on modern kernels.

Changes

New io_uring backend

• Added:

  • SocketLinuxIOUring
  • IOUringPoller

• Supports:

  • recv / send via SQEs
  • accept via SQEs
  • completion-queue–driven coroutine resumption
  • proper timeout, disconnect, and refcount handling

• Fully compatible with:

  TCPServerSocket
  TCPClientSocket
  UDPSocket

• Enabled explicitly during build:

  cmake -DUVENT_ENABLE_IO_URING=ON ..

• Fallback remains epoll when the flag is disabled.

Internal I/O path cleanup

• Separated Linux socket layer into:

  • SocketLinux (epoll)
  • SocketLinuxIOUring (io_uring)

• No impact on external APIs.

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Impact

• No public API changes.
• Existing applications work unchanged.
• Linux users can opt-in to io_uring for lower syscall overhead.
• All other platforms remain unaffected.

Notes

• io_uring requires Linux kernel 5.1+ (recommended ≥ 5.10) and liburing.
• epoll stays the default backend unless explicitly overridden.