Toward a Sweet Spot of Data Plane Programmability, Portability, and Performance: On the Scalability of Multi-Architecture P4 Pipelines

Abstract

Despite having received less attention compared to the control and application plane aspects of software-defined networking (SDN), the data plane is a critical piece of the puzzle. P4 takes SDN datapaths to the next level by unlocking deep programmability through a target-independent high-level programming language that can be compiled to run on a variety of targets (e.g., ASIC, FPGA, and GPU). This paper presents the design and evaluation of our sweet spot approach on SDN datapaths, offering three contending characteristics, namely, performance, portability, and scalability in multiple realistic scenarios. The focus is on our Multi-Architecture Compiler System for Abstract Data Planes proposal, which blends the high-level protocol-independent programmability of P4 with low-level but cross-platform (HW & SW) Application Programming Interfaces brought by OpenDataPlane, this way supporting many different vendors and architectures. Besides the performance evaluation for varying packet sizes and memory lookup tables, we investigate the impact of increasing pipeline complexity ranging from elemental L2 switching to more complex data center and border network gateways. We investigate the scalability for increasing the number of cores and evaluate a novel method for run-time core reallocation. Furthermore, we run experiments on different target platforms (e.g., ×86, ARM, 10G/100G), inducing different ways of packet mangling through specific drivers (e.g., DPDK and Netmap), and compare the results to state-of-the-art datapath alternatives.