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arXiv · 2108.06050

Accelerated Primal-Dual Algorithm for Distributed Non-convex Optimization

Shengjun Zhang·Colleen P. Bailey
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Abstract

This paper investigates accelerating the convergence of distributed optimization algorithms on non-convex problems. We propose a distributed primal-dual stochastic gradient descent~(SGD) equipped with "powerball" method to accelerate. We show that the proposed algorithm achieves the linear speedup convergence rate $\mathcal{O}(1/\sqrt{nT})$ for general smooth (possibly non-convex) cost functions. We demonstrate the efficiency of the algorithm through numerical experiments by training two-layer fully connected neural networks and convolutional neural networks on the MNIST dataset to compare with state-of-the-art distributed SGD algorithms and centralized SGD algorithms.

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Shengjun Zhang, Colleen P. Bailey. 2021-08-13. Accelerated Primal-Dual Algorithm for Distributed Non-convex Optimization. https://arxiv.org/abs/2108.06050

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