# Communication-Efficient Topologies for Decentralized Learning with O(1) Consensus Rate

arXiv: https://arxiv.org/abs/2210.07881 · HTML: https://mlsanity.com/paper/2210.07881/

## Key facts

- Cited by 25 papers in the map (data through 14 Oct 2026).
- Builds on 24 of its 52 references that are in the map.
- First posted on arXiv 14 Oct 2022.

## Builds on (most cited first, 24 of 24)

- [Deep Residual Learning for Image Recognition](https://mlsanity.com/paper/1512.03385/) (2015)
- [Can Decentralized Algorithms Outperform Centralized Algorithms? A Case Study for Decentralized Parallel Stochastic Gradient Descent](https://mlsanity.com/paper/1705.09056/) (2017)
- [A Unified Theory of Decentralized SGD with Changing Topology and Local Updates](https://mlsanity.com/paper/2003.10422/) (2020)
- [EXTRA: An Exact First-Order Algorithm for Decentralized Consensus Optimization](https://mlsanity.com/paper/1404.6264/) (2014)
- [On the Convergence of Decentralized Gradient Descent](https://mlsanity.com/paper/1310.7063/) (2013)
- [Asynchronous Decentralized Parallel Stochastic Gradient Descent](https://mlsanity.com/paper/1710.06952/) (2017)
- [Stochastic Gradient Push for Distributed Deep Learning](https://mlsanity.com/paper/1811.10792/) (2018)
- [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)
- [Network Topology and Communication-Computation Tradeoffs in Decentralized Optimization](https://mlsanity.com/paper/1709.08765/) (2017)
- [NEXT: In-Network Nonconvex Optimization](https://mlsanity.com/paper/1602.00591/) (2016)
- [Optimal algorithms for smooth and strongly convex distributed optimization in networks](https://mlsanity.com/paper/1702.08704/) (2017)
- [Distributed optimization over time-varying directed graphs](https://mlsanity.com/paper/1303.2289/) (2013)
- [An Improved Analysis of Gradient Tracking for Decentralized Machine Learning](https://mlsanity.com/paper/2202.03836/) (2022)
- [MATCHA: Speeding Up Decentralized SGD via Matching Decomposition Sampling](https://mlsanity.com/paper/1905.09435/) (2019)
- [On the Linear Convergence of the ADMM in Decentralized Consensus Optimization](https://mlsanity.com/paper/1307.5561/) (2013)
- [Exponential Graph is Provably Efficient for Decentralized Deep Training](https://mlsanity.com/paper/2110.13363/) (2021)
- [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)
- [Exact Diffusion for Distributed Optimization and Learning --- Part I: Algorithm Development](https://mlsanity.com/paper/1702.05122/) (2017)
- [A Unified and Refined Convergence Analysis for Non-Convex Decentralized Learning](https://mlsanity.com/paper/2110.09993/) (2021)
- [A Dual Approach for Optimal Algorithms in Distributed Optimization over Networks](https://mlsanity.com/paper/1809.00710/) (2018)
- [BlueFog: Make Decentralized Algorithms Practical for Optimization and Deep Learning](https://mlsanity.com/paper/2111.04287/) (2021)
- [ADOM: Accelerated Decentralized Optimization Method for Time-Varying Networks](https://mlsanity.com/paper/2102.09234/) (2021)

## Built on by (most cited first, 25 of 25)

- [Epidemic Learning: Boosting Decentralized Learning with Randomized Communication](https://mlsanity.com/paper/2310.01972/) (2023)
- [Decentralized SGD and Average-direction SAM are Asymptotically Equivalent](https://mlsanity.com/paper/2306.02913/) (2023)
- [Beyond Exponential Graph: Communication-Efficient Topologies for Decentralized Learning via Finite-time Convergence](https://mlsanity.com/paper/2305.11420/) (2023)
- [DSGD-CECA: Decentralized SGD with Communication-Optimal Exact Consensus Algorithm](https://mlsanity.com/paper/2306.00256/) (2023)
- [Boosting Asynchronous Decentralized Learning with Model Fragmentation](https://mlsanity.com/paper/2410.12918/) (2024)
- [DRACO: Decentralized Asynchronous Federated Learning over Row-Stochastic Wireless Networks](https://mlsanity.com/paper/2406.13533/) (2024)
- [Review of Mathematical Optimization in Federated Learning](https://mlsanity.com/paper/2412.01630/) (2024)
- [Scalable Decentralized Learning with Teleportation](https://mlsanity.com/paper/2501.15259/) (2025)
- [Decentralized Multi-Level Compositional Optimization Algorithms with Level-Independent Convergence Rate](https://mlsanity.com/paper/2306.03322/) (2023)
- [Communication-Efficient Federated Optimization over Semi-Decentralized Networks](https://mlsanity.com/paper/2311.18787/) (2023)
- [Dynamic Topology Optimization for Non-IID Data in Decentralized Learning](https://mlsanity.com/paper/2602.03383/) (2026)
- [Structured Cooperative Learning with Graphical Model Priors](https://mlsanity.com/paper/2306.09595/) (2023)
- [Generalizing Differentially Private Decentralized Deep Learning with Multi-Agent Consensus](https://mlsanity.com/paper/2306.13892/) (2023)
- [Federated Learning Can Find Friends That Are Advantageous](https://mlsanity.com/paper/2402.05050/) (2024)
- [Convergence of Decentralized Stochastic Subgradient-based Methods for Nonsmooth Nonconvex functions](https://mlsanity.com/paper/2403.11565/) (2024)
- [Exposing the Vulnerability of Decentralized Learning to Membership Inference Attacks Through the Lens of Graph Mixing](https://mlsanity.com/paper/2412.12837/) (2024)
- [Improved Convergence Analysis of Topology Dependence in Decentralized SGD](https://mlsanity.com/paper/2606.09154/) (2026)
- [Estimation Network Design framework for efficient distributed optimization](https://mlsanity.com/paper/2404.15273/) (2024)
- [Accelerating MoE Model Inference with Expert Sharding](https://mlsanity.com/paper/2503.08467/) (2025)
- [Distributed Learning over Arbitrary Topology: Linear Speed-Up with Polynomial Transient Time](https://mlsanity.com/paper/2503.16123/) (2025)
- [GRANITE : a Byzantine-Resilient Dynamic Gossip Learning Framework](https://mlsanity.com/paper/2504.17471/) (2025)
- [On Balancing Sparsity with Reliable Connectivity in Distributed Network Design with Random K-out Graphs](https://mlsanity.com/paper/2508.11863/) (2025)
- [Efficiency Boost in Decentralized Optimization: Reimagining Neighborhood Aggregation with Minimal Overhead](https://mlsanity.com/paper/2509.22174/) (2025)
- [Adaptive Decentralized Federated Learning for Robust Optimization](https://mlsanity.com/paper/2512.02852/) (2025)
- [Event-Triggered Gossip for Distributed Learning](https://mlsanity.com/paper/2602.19116/) (2026)

## Abstract (arXiv)

Decentralized optimization is an emerging paradigm in distributed learning in which agents achieve network-wide solutions by peer-to-peer communication without the central server. Since communication tends to be slower than computation, when each agent communicates with only a few neighboring agents per iteration, they can complete iterations faster than with more agents or a central server. However, the total number of iterations to reach a network-wide solution is affected by the speed at which the agents' information is ``mixed'' by communication. We found that popular communication topologies either have large maximum degrees (such as stars and complete graphs) or are ineffective at mixing information (such as rings and grids). To address this problem, we propose a new family of topologies, EquiTopo, which has an (almost) constant degree and a network-size-independent consensus rate that is used to measure the mixing efficiency. In the proposed family, EquiStatic has a degree of Theta(ln(n)), where n is the network size, and a series of time-dependent one-peer topologies, EquiDyn, has a constant degree of 1. We generate EquiDyn through a certain random sampling procedure. Both of them achieve an n-independent consensus rate. We apply them to decentralized SGD and decentralized gradient tracking and obtain faster communication and better convergence, theoretically and empirically. Our code is implemented through BlueFog and available at urlhttps://github.com/kexinjinnn/EquiTopo
