Adaptive Federated Optimization

Sashank J. Reddi, Zachary Charles, Manzil Zaheer, Zachary Garrett, Keith Rush, Jakub Konečný, Sanjiv Kumar, Hugh Brendan McMahan

Keywords: Federated learning, optimization, adaptive optimization, distributed optimization

Abstract: Federated learning is a distributed machine learning paradigm in which a large number of clients coordinate with a central server to learn a model without sharing their own training data. Standard federated optimization methods such as Federated Averaging (FedAvg) are often difficult to tune and exhibit unfavorable convergence behavior. In non-federated settings, adaptive optimization methods have had notable success in combating such issues. In this work, we propose federated versions of adaptive optimizers, including Adagrad, Adam, and Yogi, and analyze their convergence in the presence of heterogeneous data for general non-convex settings. Our results highlight the interplay between client heterogeneity and communication efficiency. We also perform extensive experiments on these methods and show that the use of adaptive optimizers can significantly improve the performance of federated learning.

One-sentence Summary: We propose adaptive federated optimization techniques, and highlight their improved performance over popular methods such as FedAvg.

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Code: [ google-research/federated](https://github.com/google-research/federated/tree/master/optimization) + [ 4 community implementations](https://paperswithcode.com/paper/?openreview=LkFG3lB13U5)

Data: [CIFAR-10](https://paperswithcode.com/dataset/cifar-10), [CIFAR-100](https://paperswithcode.com/dataset/cifar-100)

Community Implementations: [ 2 code implementations](https://www.catalyzex.com/paper/arxiv:2003.00295/code)