## Communication-Efficient Network-Distributed Optimization with Differential-Coded Compressors

2019-01-01
##### Authors
Zhang, Xin
Zhu, Zhengyuan
Liu, Jia
Zhu, Zhengyuan
Bentley, Elizabeth
##### Organizational Units
Computer Science
Organizational Unit
Statistics
Organizational Unit
##### Department
Computer ScienceStatistics
##### Abstract

Network-distributed optimization has attracted significant attention in recent years due to its ever-increasing applications. However, the classic decentralized gradient descent (DGD) algorithm is communication-inefficient for large-scale and high-dimensional network-distributed optimization problems. To address this challenge, many compressed DGD-based algorithms have been proposed. However, most of the existing works have high complexity and assume compressors with bounded noise power. To overcome these limitations, in this paper, we propose a new differential-coded compressed DGD (DC-DGD) algorithm. The key features of DC-DGD include: i) DC-DGD works with general SNR-constrained compressors, relaxing the bounded noise power assumption; ii) The differential-coded design entails the same convergence rate as the original DGD algorithm; and iii) DC-DGD has the same low-complexity structure as the original DGD due to a {\em self-noise-reduction effect}. Moreover, the above features inspire us to develop a hybrid compression scheme that offers a systematic mechanism to minimize the communication cost. Finally, we conduct extensive experiments to verify the efficacy of the proposed DC-DGD and hybrid compressor.

##### Comments

This is a pre-print of the proceeding Zhang, Xin, Jia Liu, Zhengyuan Zhu, and Elizabeth S. Bentley. "Communication-Efficient Network-Distributed Optimization with Differential-Coded Compressors." arXiv preprint arXiv:1912.03208 (2019).