Developing normalization schemes for data isolated distributed deep learning

Distributed deep learning is an important and indispensable direction in the field of deep learning research. Earlier research has proposed many algorithms or techniques on accelerating distributed neural network training. This study discusses a new distributed training scenario, namely data isolated distributed deep learning. Specifically, each node has its own local data and cannot be shared for some reasons. However, in order to ensure the generalization of the model, the goal is to train a global model that required learning all the data, not just based on data from a local node. At this time, distributed training with data isolation is needed. An obvious challenge for distributed deep learning in this scenario is that the distribution of training data used by each node could be highly imbalanced because of data isolation. This brings difficulty to the normalization process in neural network training, because the traditional batch normalization (BN) method will fail under this kind of data imbalanced scenario. At this time, distributed training with data isolation is needed. Aiming at such data isolation scenarios, this study proposes a comprehensive data isolation deep learning scheme. Specifically, synchronous stochastic gradient descent algorithm is used for data exchange during training, and provides several normalization approaches to the problem of BN failure caused by data imbalance. Experimental results show the efficiency and accuracy of the proposed data isolated distributed deep learning scheme.