# Proximal and Federated Random Reshuffling

arXiv: https://arxiv.org/abs/2102.06704 · HTML: https://mlsanity.com/paper/2102.06704/

## Key facts

- Cited by 33 papers in the map (data through 14 Oct 2026).
- Builds on 27 of its 54 references that are in the map.
- First posted on arXiv 12 Feb 2021.

## Builds on (most cited first, 27 of 27)

- [Communication-Efficient Learning of Deep Networks from Decentralized Data](https://mlsanity.com/paper/1602.05629/) (2016)
- [Advances and Open Problems in Federated Learning](https://mlsanity.com/paper/1912.04977/) (2019)
- [Federated Learning: Strategies for Improving Communication Efficiency](https://mlsanity.com/paper/1610.05492/) (2016)
- [Linear Convergence of Gradient and Proximal-Gradient Methods Under the Polyak-Lojasiewicz Condition](https://mlsanity.com/paper/1608.04636/) (2016)
- [Tighter Theory for Local SGD on Identical and Heterogeneous Data](https://mlsanity.com/paper/1909.04746/) (2019)
- [SGD: General Analysis and Improved Rates](https://mlsanity.com/paper/1901.09401/) (2019)
- [Better Theory for SGD in the Nonconvex World](https://mlsanity.com/paper/2002.03329/) (2020)
- [Minibatch vs Local SGD for Heterogeneous Distributed Learning](https://mlsanity.com/paper/2006.04735/) (2020)
- [Stochastic Gradient Descent, Weighted Sampling, and the Randomized Kaczmarz algorithm](https://mlsanity.com/paper/1310.5715/) (2013)
- [Random Reshuffling: Simple Analysis with Vast Improvements](https://mlsanity.com/paper/2006.05988/) (2020)
- [Stochastic Optimization with Importance Sampling](https://mlsanity.com/paper/1401.2753/) (2014)
- [A Unified Theory of SGD: Variance Reduction, Sampling, Quantization and Coordinate Descent](https://mlsanity.com/paper/1905.11261/) (2019)
- [Unified Optimal Analysis of the (Stochastic) Gradient Method](https://mlsanity.com/paper/1907.04232/) (2019)
- [First Analysis of Local GD on Heterogeneous Data](https://mlsanity.com/paper/1909.04715/) (2019)
- [Why Random Reshuffling Beats Stochastic Gradient Descent](https://mlsanity.com/paper/1510.08560/) (2015)
- [Random Shuffling Beats SGD after Finite Epochs](https://mlsanity.com/paper/1806.10077/) (2018)
- [SGD without Replacement: Sharper Rates for General Smooth Convex Functions](https://mlsanity.com/paper/1903.01463/) (2019)
- [SGD with shuffling: optimal rates without component convexity and large epoch requirements](https://mlsanity.com/paper/2006.06946/) (2020)
- [Federated Composite Optimization](https://mlsanity.com/paper/2011.08474/) (2020)
- [Incremental Gradient, Subgradient, and Proximal Methods for Convex Optimization: A Survey](https://mlsanity.com/paper/1507.01030/) (2015)
- [ProxSARAH: An Efficient Algorithmic Framework for Stochastic Composite Nonconvex Optimization](https://mlsanity.com/paper/1902.05679/) (2019)
- [The Complexity of Finding Stationary Points with Stochastic Gradient Descent](https://mlsanity.com/paper/1910.01845/) (2019)
- [Stochastic Quasi-Gradient Methods: Variance Reduction via Jacobian Sketching](https://mlsanity.com/paper/1805.02632/) (2018)
- [Stochastic subgradient method converges at the rate O(k-1/4) on weakly convex functions](https://mlsanity.com/paper/1802.02988/) (2018)
- [The Practicality of Stochastic Optimization in Imaging Inverse Problems](https://mlsanity.com/paper/1910.10100/) (2019)
- [A Coordinate Descent Primal-Dual Algorithm and Application to Distributed Asynchronous Optimization](https://mlsanity.com/paper/1407.0898/) (2014)
- [ASVRG: Accelerated Proximal SVRG](https://mlsanity.com/paper/1810.03105/) (2018)

## Built on by (most cited first, 30 of 33)

- [FedNL: Making Newton-Type Methods Applicable to Federated Learning](https://mlsanity.com/paper/2106.02969/) (2021)
- [Minibatch vs Local SGD with Shuffling: Tight Convergence Bounds and Beyond](https://mlsanity.com/paper/2110.10342/) (2021)
- [Server-Side Stepsizes and Sampling Without Replacement Provably Help in Federated Optimization](https://mlsanity.com/paper/2201.11066/) (2022)
- [FedNew: A Communication-Efficient and Privacy-Preserving Newton-Type Method for Federated Learning](https://mlsanity.com/paper/2206.08829/) (2022)
- [FedShuffle: Recipes for Better Use of Local Work in Federated Learning](https://mlsanity.com/paper/2204.13169/) (2022)
- [Communication Acceleration of Local Gradient Methods via an Accelerated Primal-Dual Algorithm with Inexact Prox](https://mlsanity.com/paper/2207.03957/) (2022)
- [Federated Optimization Algorithms with Random Reshuffling and Gradient Compression](https://mlsanity.com/paper/2206.07021/) (2022)
- [Faster federated optimization under second-order similarity](https://mlsanity.com/paper/2209.02257/) (2022)
- [Federated Learning with Regularized Client Participation](https://mlsanity.com/paper/2302.03662/) (2023)
- [Improved Analysis and Rates for Variance Reduction under Without-replacement Sampling Orders](https://mlsanity.com/paper/2104.12112/) (2021)
- [Randomized Asymmetric Chain of LoRA: The First Meaningful Theoretical Framework for Low-Rank Adaptation](https://mlsanity.com/paper/2410.08305/) (2024)
- [Federated Random Reshuffling with Compression and Variance Reduction](https://mlsanity.com/paper/2205.03914/) (2022)
- [On the Last-Iterate Convergence of Shuffling Gradient Methods](https://mlsanity.com/paper/2403.07723/) (2024)
- [Nesterov Accelerated Shuffling Gradient Method for Convex Optimization](https://mlsanity.com/paper/2202.03525/) (2022)
- [Sampling without Replacement Leads to Faster Rates in Finite-Sum Minimax Optimization](https://mlsanity.com/paper/2206.02953/) (2022)
- [Last Iterate Convergence of Incremental Methods and Applications in Continual Learning](https://mlsanity.com/paper/2403.06873/) (2024)
- [Understanding Outer Optimizers in Local SGD: Learning Rates, Momentum, and Acceleration](https://mlsanity.com/paper/2509.10439/) (2025)
- [On Convergence of Incremental Gradient for Non-Convex Smooth Functions](https://mlsanity.com/paper/2305.19259/) (2023)
- [A New Random Reshuffling Method for Nonsmooth Nonconvex Finite-sum Optimization](https://mlsanity.com/paper/2312.01047/) (2023)
- [A Unified Theory of Stochastic Proximal Point Methods without Smoothness](https://mlsanity.com/paper/2405.15941/) (2024)
- [Asynchronous Federated Learning: A Scalable Approach for Decentralized Machine Learning](https://mlsanity.com/paper/2412.17723/) (2024)
- [Distributed stochastic proximal algorithm with random reshuffling for non-smooth finite-sum optimization](https://mlsanity.com/paper/2111.03820/) (2021)
- [Cohort Squeeze: Beyond a Single Communication Round per Cohort in Cross-Device Federated Learning](https://mlsanity.com/paper/2406.01115/) (2024)
- [First Provable Guarantees for Practical Private FL: Beyond Restrictive Assumptions](https://mlsanity.com/paper/2512.21521/) (2025)
- [Better Methods and Theory for Federated Learning: Compression, Client Selection and Heterogeneity](https://mlsanity.com/paper/2207.00392/) (2022)
- [Convergence of ease-controlled Random Reshuffling gradient Algorithms under Lipschitz smoothness](https://mlsanity.com/paper/2212.01848/) (2022)
- [Linear Convergence of Reshuffling Kaczmarz Methods With Sparse Constraints](https://mlsanity.com/paper/2304.10123/) (2023)
- [Stochastic optimization with arbitrary recurrent data sampling](https://mlsanity.com/paper/2401.07694/) (2024)
- [Shuffling Gradient-Based Methods for Nonconvex-Concave Minimax Optimization](https://mlsanity.com/paper/2410.22297/) (2024)
- [Beyond adaptive gradient: Fast-Controlled Minibatch Algorithm for large-scale optimization](https://mlsanity.com/paper/2411.15795/) (2024)

## Abstract (arXiv)

Random Reshuffling (RR), also known as Stochastic Gradient Descent (SGD) without replacement, is a popular and theoretically grounded method for finite-sum minimization. We propose two new algorithms: Proximal and Federated Random Reshuffing (ProxRR and FedRR). The first algorithm, ProxRR, solves composite convex finite-sum minimization problems in which the objective is the sum of a (potentially non-smooth) convex regularizer and an average of n smooth objectives. We obtain the second algorithm, FedRR, as a special case of ProxRR applied to a reformulation of distributed problems with either homogeneous or heterogeneous data. We study the algorithms' convergence properties with constant and decreasing stepsizes, and show that they have considerable advantages over Proximal and Local SGD. In particular, our methods have superior complexities and ProxRR evaluates the proximal operator once per epoch only. When the proximal operator is expensive to compute, this small difference makes ProxRR up to n times faster than algorithms that evaluate the proximal operator in every iteration. We give examples of practical optimization tasks where the proximal operator is difficult to compute and ProxRR has a clear advantage. Finally, we corroborate our results with experiments on real data sets.
