Randomized dual proximal gradient for large-scale distributed optimization

Ivano Notarnicola; Giuseppe Notarstefano

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arXiv · 1609.05713

Randomized dual proximal gradient for large-scale distributed optimization

Ivano Notarnicola·Giuseppe Notarstefano

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Abstract

In this paper we consider distributed optimization problems in which the cost function is separable (i.e., a sum of possibly non-smooth functions all sharing a common variable) and can be split into a strongly convex term and a convex one. The second term is typically used to encode constraints or to regularize the solution. We propose an asynchronous, distributed optimization algorithm over an undirected topology, based on a proximal gradient update on the dual problem. We show that by means of a proper choice of primal variables, the dual problem is separable and the dual variables can be stacked into separate blocks. This allows us to show that a distributed gossip update can be obtained by means of a randomized block-coordinate proximal gradient on the dual function.

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Ivano Notarnicola, Giuseppe Notarstefano. 2016-09-19. Randomized dual proximal gradient for large-scale distributed optimization. https://arxiv.org/abs/1609.05713

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