Telecommunication operators are massively moving their network functions in small data centers at the edge of the network, which are becoming increasingly common. However, the high performance provided by commonly used technologies for data plane processing such as DPDK, based on kernel-bypass primitives, comes at the cost of rigid resource partitioning. This is unsuitable for edge data centers, in which efficiency demands both general-purpose applications and data-plane telco workloads to be executed on the same (shared) physical machines. In this respect, eBPF/XDP looks a more appealing solution, thanks to its capability to process packets in the kernel, achieving a higher level of integration with non-data plane applications albeit with lower performance than DPDK. In this paper we leverage the recent introduction of AF_XDP, an XDP-based technology that allows to efficiently steer packets in user space, to provide a thorough comparison of user space vs in-kernel packet processing in typical scenarios of a data center at the edge of the network. Our results provide useful insights on how to select and combine these technologies in order to improve overall throughput and optimize resource usage.

电信运营商正在大规模地将其网络功能转移到网络边缘的小型数据中心，这种情况正变得越来越普遍。然而，基于内核旁路原语的 DPDK 等常用数据平面处理技术提供的高性能是以严格的资源分区为代价的。这不适合边缘数据中心，其中效率要求通用应用程序和数据平面电信工作负载在同一（共享）物理机器上执行。在这方面，eBPF/XDP 看起来是一个更有吸引力的解决方案，这要归功于它在内核中处理数据包的能力，实现了与非数据平面应用程序的更高级别的集成，尽管性能低于 DPDK。在本文中，我们利用了最近引入的 AF_XDP，一种基于 XDP 的技术，允许在用户空间中有效地引导数据包，以在网络边缘数据中心的典型场景中提供用户空间与内核数据包处理的全面比较。我们的结果提供了关于如何选择和组合这些技术以提高整体吞吐量和优化资源使用的有用见解。