swCaffe: A Parallel Framework for Accelerating Deep Learning Applications on Sunway TaihuLight

This paper reports our efforts on swCaffe, a high-efficient parallel framework for accelerating deep neural networks (DNNs) training on Sunway TaihuLight, one of the fastest supercomputers in the world that adopts a unique heterogeneous many-core architecture. First, we point out some insightful principles to fully exploit the performance of the innovative many-core architecture. Second, we propose a set of optimization strategies for redesigning a variety of neural network layers based on Caffe. Third, we put forward a topology-aware parameter synchronization scheme to scale the synchronous Stochastic Gradient Descent (SGD) method to multiple processors efficiently. We evaluate our framework by training a variety of widely used neural networks with the ImageNet dataset. On a single node, swCaffe can achieve 23%˜119% overall performance compared with Caffe running on K40m GPU. As compared with Caffe on CPU, swCaffe runs 3.04˜7.84× faster on all networks. When training ResNet50 and AlexNet with 1024 nodes, swCaffe can achieve up to 715.45× and 928.15× speedup.