Decentralized Partial Model Personalization With Guaranteed Nonconvex Convergence

Compared with general Federated Learning (FL), Decentralized FL (DFL) has diminished central communication burdens and lower risks of disruption. To be compatible with real-world scenarios, some existing works produce several local personalized models rather than a universal model for all edge devices. However, they still suffer from inferior performance due to the full model aggregation in heterogeneous datasets. Therefore, we propose a DFL framework DFedMDC through partial model personalization, which can adapt to resource-heterogeneous environments (e.g., the Internet of Things (IoT)). Specifically, it personalizes the “right” components of local models and trains the shared modeluiand personal modelvialternately in each clienti. To further accelerate the convergence process, we propose DFedSMDC with properly directed noise perturbation into the gradient update. Theoretically, we provide convergence analysis of both algorithms in the general non-convex setting. It can shed light on how vital factors affect the convergence rate, such as these alternate updates of partial modelsui,vi, data heterogeneity δ2as well as various communication topologies (characterized by the spectral gap 1 − λ). Empirically, we confirm the state-of-the-art (SOTA) superiority of the proposed methods on several real-world datasets with various data distributions, relative to both SOTA personalized FL (PFL) and DFL baselines.