HyperFLoRA: Federated Learning with Instantaneous Personalization
Qikai Lu, Di Niu, Mohammadamin Samadi Khoshkho, Baochun Li · Society for Industrial and Applied Mathematics eBooks · 2024
Federated learning is a decentralized approach to training machine learning models while preserving data privacy. To accommodate data heterogeneity among clients, a longstanding issue in Federated Learning, many Personalized Federated Learning (PFL) strategies decompose each client model into global modules, which are collaboratively learned by all clients and the server, and local modules, which are only trained locally on private data. While these strategies require every client to participate in training, in reality, many client devices lack sufficient data or computing resources to perform meaningful local training, making it difficult to achieve personalization for every client. In this paper, we present HyperFLoRA, a PFL framework that leverages knowledge learned from training-capable clients to enable the immediate creation of personalized models for training-incapable or new clients. HyperFLoRA uses adapters for personalization to minimize communication costs and client training workload while employing a trainable hypernetwork to generate personalized adapter weights for each client using minimal client statistical information. From experiments conducted on both convolutional and Transformer neural networks, HyperFLoRA can achieve superior model personalization performance for new clients that did not participate in training than conventional PFL methods, while significantly reducing training-related communication costs and client workload.