SCU: A Hardware Accelerator for Smart Contract Execution

Smart contracts and the blockchain have recently been widely used in many application fields. Current smart contracts are executed on general-purpose CPUs and still have a large room to improve performance. In this paper, we first analyze the most popular public blockchain platform Ethereum and characterize smart contracts running on its ecosystem. After identifying its performance limitations, we propose a heterogeneous processor Smart Contract Unit (SCU), which is a hardware-based accelerator in place of the current EVM design. With our proposed novel RISC-style SCU ISA and heterogeneous architecture, SCU can leverage instruction-level parallelism and transaction-level parallelism during smart contract processing and boost its execution performance. Furthermore, SCU can be configured and adapted to different workloads in order to remove bottlenecks. We implement and evaluate the proposed SCU design on a Xilinx FPGA platform. Our design achieves a significant speedup compared to the software implementation on an Intel CPU and runs a few times faster than state-of-the-art design.