Misc,

Adding vs. Averaging in Distributed Primal-Dual Optimization

, , , , , and .
(2015)cite arxiv:1502.03508Comment: ICML 2015: JMLR W&CP volume37, Proceedings of The 32nd International Conference on Machine Learning, pp. 1973-1982.

Abstract

Distributed optimization methods for large-scale machine learning suffer from a communication bottleneck. It is difficult to reduce this bottleneck while still efficiently and accurately aggregating partial work from different machines. In this paper, we present a novel generalization of the recent communication-efficient primal-dual framework (CoCoA) for distributed optimization. Our framework, CoCoA+, allows for additive combination of local updates to the global parameters at each iteration, whereas previous schemes with convergence guarantees only allow conservative averaging. We give stronger (primal-dual) convergence rate guarantees for both CoCoA as well as our new variants, and generalize the theory for both methods to cover non-smooth convex loss functions. We provide an extensive experimental comparison that shows the markedly improved performance of CoCoA+ on several real-world distributed datasets, especially when scaling up the number of machines.

Tags

Users

  • @alrigazzi

Comments and Reviews