Understanding the Idiosyncrasies of Emerging BlueField DPUs
Arjun Kashyap, Yuke Li, Darren Ng, Xiaoyi Lu · 2025
Data Processing Units (DPUs) are becoming available in datacenter environments to offload/accelerate workloads from the host.However, a comprehensive analysis is required to help users determine how to effectively utilize DPUs for their workloads, considering the various configurations and generations available.To fill in this gap, we conduct a fair and rigorous characterization by performing 15 benchmarking tests to demonstrate the evolution of representative SoC-based DPUs, specifically NVIDIA's BlueField-1, BlueField-2, and BlueField-3.Our work surfaces several idiosyncrasies across three key characterization dimensions-network, DMA engine, and memory.For network, we exhaustively test two major DPU modes-on-path (and five submodes) and offpath modes.We develop DPUDMABench, a microbenchmark suite to systematically analyze different data exchange primitives supported by DPU's DMA engine.We also conduct two application case studies examining the DPU mode's performance impact on TCP/IP and RDMA-based key-value stores (MICA and HERD).Based on our multi-generational DPU characterization, we identify and summarize 14 major idiosyncrasies, along with providing guidelines for optimal system and future hardware design.