Distributed Graph Neural Network Training
摘要
In this chapter, we present our distributed GNN training solution. Specifically, to mitigate the communication overhead induced by expensive data movement across workers, we propose Sancus, a staleness-aware, communication-avoiding, decentralized GNN system. By introducing a set of novel bounded embedding staleness metrics and adaptively skipping broadcasts, Sancus abstracts decentralized GNN computation as sequential matrix multiplication and leverages cached historical embeddings. Theoretically, we establish bounded approximation errors for both embeddings and gradients, together with convergence guarantees. Empirically, we evaluate Sancus with common GNN models under diverse system configurations on large-scale benchmark datasets. Compared to SOTA works, Sancus avoids up to 74% communication and achieves at least \(1.86\times \) higher throughput on average, without accuracy loss.