Towards Robust and Efficient Cloud-Edge Elastic Model Adaptation via Selective Entropy Distillation

Abstract: The conventional deep learning paradigm often involves training a deep model on a server and then deploying the model or its distilled ones to resource-limited edge devices. Usually, the models shall remain fixed once deployed (at least for some period) due to the potential high cost of model adaptation for both the server and edge sides. However, in many real-world scenarios, the test environments may change dynamically (known as distribution shifts), which often results in degraded performance. Thus, one has to adapt the edge models promptly to attain promising performance. Moreover, with the increasing data collected at the edge, this paradigm also fails to further adapt the cloud model for better performance. To address these, we encounter two primary challenges: 1) the edge model has limited computation power and may only support forward propagation; 2) the data transmission budget between cloud and edge devices is limited in latency-sensitive scenarios. In this paper, we establish a Cloud-Edge Elastic Model Adaptation (CEMA) paradigm in which the edge models only need to perform forward propagation and the edge models can be adapted online. In our CEMA, to reduce the communication burden, we devise two criteria to exclude unnecessary samples from uploading to the cloud, i.e., dynamic unreliable and low-informative sample exclusion. Based on the uploaded samples, we update and distribute the affine parameters of normalization layers by distilling from the stronger foundation model to the edge model with a sample replay strategy. Extensive experimental results on ImageNet-C and ImageNet-R verify the effectiveness of our CEMA.

• The paper introduces the CEMA framework that uses selective entropy distillation for efficient online adaptation of edge models.
• It leverages replay-based knowledge distillation from a robust cloud model to tackle distribution shifts in edge environments.
• Experimental results demonstrate a 60% reduction in communication overhead while maintaining strong performance on ImageNet-C and ImageNet-R.

Selective Entropy Distillation for Efficient Cloud-Edge Model Adaptation

Introduction

The paper proposes a Cloud-Edge Elastic Model Adaptation (CEMA) framework designed to address two primary challenges in deploying deep neural networks (DNNs) in real-world edge devices: limited computation power on the edge and constrained data transmission budgets between cloud and edge devices. Given the dynamic nature of real-world environments, edge models often suffer from degraded performance due to distribution shifts in the test data. Traditional methods for updating these models either lack practicality due to resource constraints on edge devices or introduce heavy communication overheads when adapting models in the cloud. The paper introduces an innovative paradigm for online adaptation of edge models that leverages sample filtration based on dynamic and static entropy thresholds, minimizing unnecessary data transmission, and utilizes replay-based knowledge distillation from a more powerful foundation model in the cloud for efficient and effective adaptation.

Cloud-Edge Communication-Efficient Model Adaptation

The CEMA framework is designed for scenarios where edge devices confront distribution-shifted test samples. It effectively partitions the adaptation task between edge devices and the cloud, exploiting their computational and data resources. The paper delineates a selective sample uploading mechanism aimed at reducing communication overhead by filtering out high-entropy (unreliable) and low-entropy (low-informative) samples. Moreover, it elaborates on a strategy where the edge model is adapted in the cloud through knowledge distillation, guided by the stronger foundation model. A distinctive aspect of this process is the use of a replay buffer to enhance data utilization, allowing the system to learn from both newly uploaded and previously encountered samples.

Main Contributions

The paper's main contributions are threefold:

1. Introduction of the Cloud-Edge Elastic Model Adaptation (CEMA) paradigm, a novel and practical framework for efficient model adaptation in distributed environments.
2. Proposal of a replay-based entropy distillation method that facilitates the adaptation of edge models to new environments dynamically, leveraging a foundation model in the cloud.
3. Implementation of entropy-based criteria for sample selection, significantly reducing communication costs by excluding samples that are deemed unreliable or low-informative, verified through experiments to lower communication costs by 60% compared to state-of-the-art methods on ImageNet-C.

Experimental Results

The efficacy of the CEMA paradigm is demonstrated through extensive experiments on ImageNet-C and ImageNet-R, showcasing its superiority in adapting edge models under distribution shifts. Notably, the framework achieves commendable performance with substantially lower data transmission, addressing the practical challenge of updating edge models in latency-sensitive applications. The results illustrate the potential of CEMA in real-world deployments, where maintaining high model performance with minimal communication overhead is paramount.

Future Directions

The paper speculates on several avenues for future research, including refining the entropy-based sample selection criteria for further reduction in communication costs and exploring the applicability of CEMA across a broader range of edge computing scenarios. Another interesting direction could involve investigating the impact of different types of foundation models on the adaptation performance and efficiency of edge models.

Conclusion

The paper presents a formidable approach towards robust and efficient model adaptation in cloud-edge deployments, addressing critical challenges in real-world AI applications. By carefully designing mechanisms for selective sample transmission and leveraging advanced knowledge distillation techniques, it sets a new benchmark for practical, communication-efficient model adaptation strategies. The proposed CEMA paradigm holds significant promise for enhancing the performance of edge AI systems, paving the way for more adaptive, efficient, and scalable deployments in diverse applications.