FANNS: An FPGA-Based Approximate Nearest-Neighbor Search Accelerator

Approximate nearest-neighbor search (ANNS) based on high-dimensional vectors has been extensively utilized in data science and neural networks. However, deploying ANNS in production systems requires minimal redundant computation, high recall rates, and low on-chip memory usage, which existing hardware accelerators fail to offer. We propose FANNS, a solution for ANNS based on high-dimensional vectors that can eliminate redundant computations and reuse on-chip data. Extensive evaluations show that FANNS achieves an average of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$184.1\times $ </tex-math></inline-formula>, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$33.0\times $ </tex-math></inline-formula>, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.9\times $ </tex-math></inline-formula>, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.5\times $ </tex-math></inline-formula> better energy efficiency than CPUs, GPUs, and two state-of-the-art ANNS architectures, i.e., DF-GAS and Vstore, respectively.