# A One-Sample Decentralized Proximal Algorithm for Non-Convex Stochastic Composite Optimization

arXiv: https://arxiv.org/abs/2302.09766 · HTML: https://mlsanity.com/paper/2302.09766/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- Builds on 28 of its 50 references that are in the map.
- First posted on arXiv 20 Feb 2023.

## Builds on (most cited first, 28 of 28)

- [PyTorch: An Imperative Style, High-Performance Deep Learning Library](https://mlsanity.com/paper/1912.01703/) (2019)
- [Can Decentralized Algorithms Outperform Centralized Algorithms? A Case Study for Decentralized Parallel Stochastic Gradient Descent](https://mlsanity.com/paper/1705.09056/) (2017)
- [Lower Bounds for Non-Convex Stochastic Optimization](https://mlsanity.com/paper/1912.02365/) (2019)
- [Momentum-Based Variance Reduction in Non-Convex SGD](https://mlsanity.com/paper/1905.10018/) (2019)
- [Achieving Geometric Convergence for Distributed Optimization over Time-Varying Graphs](https://mlsanity.com/paper/1607.03218/) (2016)
- [D2: Decentralized Training over Decentralized Data](https://mlsanity.com/paper/1803.07068/) (2018)
- [NEXT: In-Network Nonconvex Optimization](https://mlsanity.com/paper/1602.00591/) (2016)
- [Distributed Stochastic Gradient Tracking Methods](https://mlsanity.com/paper/1805.11454/) (2018)
- [Variance-Reduced Methods for Machine Learning](https://mlsanity.com/paper/2010.00892/) (2020)
- [An Improved Analysis of Gradient Tracking for Decentralized Machine Learning](https://mlsanity.com/paper/2202.03836/) (2022)
- [Optimal Complexity in Decentralized Training](https://mlsanity.com/paper/2006.08085/) (2020)
- [A Single Time-Scale Stochastic Approximation Method for Nested Stochastic Optimization](https://mlsanity.com/paper/1812.01094/) (2018)
- [An improved convergence analysis for decentralized online stochastic non-convex optimization](https://mlsanity.com/paper/2008.04195/) (2020)
- [A decentralized proximal-gradient method with network independent step-sizes and separated convergence rates](https://mlsanity.com/paper/1704.07807/) (2017)
- [On Nonconvex Decentralized Gradient Descent](https://mlsanity.com/paper/1608.05766/) (2016)
- [ProxSARAH: An Efficient Algorithmic Framework for Stochastic Composite Nonconvex Optimization](https://mlsanity.com/paper/1902.05679/) (2019)
- [Distributed Nonconvex Constrained Optimization over Time-Varying Digraphs](https://mlsanity.com/paper/1809.01106/) (2018)
- [Conditional Gradient Method for Stochastic Submodular Maximization: Closing the Gap](https://mlsanity.com/paper/1711.01660/) (2017)
- [Distributed Algorithms for Composite Optimization: Unified Framework and Convergence Analysis](https://mlsanity.com/paper/2002.11534/) (2020)
- [A Stochastic Proximal Gradient Framework for Decentralized Non-Convex Composite Optimization: Topology-Independent Sample Complexity and Communication Efficiency](https://mlsanity.com/paper/2110.01594/) (2021)
- [On the Convergence of Consensus Algorithms with Markovian Noise and Gradient Bias](https://mlsanity.com/paper/2008.07841/) (2020)
- [Proximal Stochastic Recursive Momentum Methods for Nonconvex Composite Decentralized Optimization](https://mlsanity.com/paper/2211.11954/) (2022)
- [Distributed Stochastic Consensus Optimization with Momentum for Nonconvex Nonsmooth Problems](https://mlsanity.com/paper/2011.05082/) (2020)
- [Decentralized Composite Optimization with Compression](https://mlsanity.com/paper/2108.04448/) (2021)
- [Parallel Selective Algorithms for Big Data Optimization](https://mlsanity.com/paper/1402.5521/) (2014)
- [A Linearly Convergent Proximal Gradient Algorithm for Decentralized Optimization](https://mlsanity.com/paper/1905.07996/) (2019)
- [Distributed constrained optimization and consensus in uncertain networks via proximal minimization](https://mlsanity.com/paper/1603.02239/) (2016)
- [A Unifying Approximate Method of Multipliers for Distributed Composite Optimization](https://mlsanity.com/paper/2009.12732/) (2020)

## Built on by (most cited first, 4 of 4)

- [Compressed Decentralized Momentum Stochastic Gradient Methods for Nonconvex Optimization](https://mlsanity.com/paper/2508.04950/) (2025)
- [Convergence of Decentralized Stochastic Subgradient-based Methods for Nonsmooth Nonconvex functions](https://mlsanity.com/paper/2403.11565/) (2024)
- [Fully First-Order Methods for Decentralized Bilevel Optimization](https://mlsanity.com/paper/2410.19319/) (2024)
- [Decentralized Nonconvex Composite Federated Learning with Gradient Tracking and Momentum](https://mlsanity.com/paper/2504.12742/) (2025)

## Abstract (arXiv)

We focus on decentralized stochastic non-convex optimization, where n agents work together to optimize a composite objective function which is a sum of a smooth term and a non-smooth convex term. To solve this problem, we propose two single-time scale algorithms: Prox-DASA and Prox-DASA-GT. These algorithms can find ε-stationary points in O(n-1ε-2) iterations using constant batch sizes (i.e., O(1)). Unlike prior work, our algorithms achieve comparable complexity without requiring large batch sizes, more complex per-iteration operations (such as double loops), or stronger assumptions. Our theoretical findings are supported by extensive numerical experiments, which demonstrate the superiority of our algorithms over previous approaches. Our code is available at https://github.com/xuxingc/ProxDASA.
