The Graph Convolutional Network (GCN) model and its variants are powerful
graph embedding tools for facilitating classification and clustering on graphs.
However, a major challenge is to reduce the complexity of layered GCNs and make
them parallelizable and scalable on very large graphs -- state-of the art
techniques are unable to achieve scalability without losing accuracy and
efficiency. In this paper, we propose novel parallelization techniques for
graph sampling-based GCNs that achieve superior scalable performance on very
large graphs without compromising accuracy. Specifically, our GCN guarantees
work-efficient training and produces order of magnitude savings in computation
and communication. To scale GCN training on tightly-coupled shared memory
systems, we develop parallelization strategies for the key steps in training:
For the graph sampling step, we exploit parallelism within and across multiple
sampling instances, and devise an efficient data structure for concurrent
accesses that provides theoretical guarantee of near-linear speedup with number
of processing units. For the feature propagation step within the sampled graph,
we improve cache utilization and reduce DRAM communication by data
partitioning. We prove that our partitioning strategy is a 2-approximation for
minimizing the communication time compared to the optimal strategy. We
demonstrate that our parallel graph embedding outperforms state-of-the-art
methods in scalability (with respect to number of processors, graph size and
GCN model size), efficiency and accuracy on several large datasets. On a
40-core Xeon platform, our parallel training achieves $64\times$ speedup (with
AVX) in the sampling step and $25\times$ speedup in the feature propagation
step, compared to the serial implementation, resulting in a net speedup of
$21\times$.

本文提出了并行化技术，为图采样 GCN 提供卓越的可扩展性性能，在不妥协准确性的情况下，在非常大的图上实现了优秀的性能。具体地，我们保证了 GCN 的高效训练，并在计算和通信方面节约了数量级的开销，同时，我们的并行图嵌入在可扩展性、效率和准确性方面优于现有的方法。