GNNerator: A Hardware/Software Framework for Accelerating Graph Neural Networks

Graph Neural Networks (GNNs) apply deep learning to inputs represented as graphs. They use fully-connected layers to extract features from the nodes/edges of a graph and aggregate these features using message passing between nodes, thereby combining two distinct computational patterns: dense, regular computations and sparse, irregular computations. To address the computational challenges posed by GNNs, we propose GNNERATOR, an accelerator with heterogeneous compute engines optimized for these two patterns. Further, we propose feature-blocking, a novel GNN dataflow that beneficially trades off irregular memory accesses during aggregation for regular memory accesses during feature extraction. We show that GNNERATOR achieves speedups of 5.7-37x over an NVIDIA RTX 2080-Ti, and 2.3x-3.8x over HyGCN, a state-of-the-art GNN accelerator.