[edit]
Domain-Specific Expert Pruning for Mixture-of-Experts LLMs
Proceedings of The Second AAAI Bridge Program on AI for Medicine and Healthcare, PMLR 317:313-321, 2026.
Abstract
Mixture-of-Experts (MoE) architectures have emerged as a promising paradigm for scaling large language models (LLMs) with sparse activation of task-specific experts. Despite their computational efficiency during inference, the massive overall parameter footprint of MoE models (e.g., GPT-4) introduces critical challenges for practical deployment. Current pruning approaches often fail to address two inherent characteristics of MoE systems: 1).intra-layer expert homogeneity where experts within the same MoE layer exhibit functional redundancy, and 2). inter-layer similarity patterns where deeper layers tend to contain progressively more homogeneous experts. To tackle these issues, we propose Cluster-driven Domain-Specific Expert Pruning (C-PRUNE), a novel two-stage framework for adaptive task-specific compression of MoE LLMs. C-PRUNE operates through layer-wise expert clustering, which groups functionally similar experts within each MoE layer using parameter similarity metrics, followed by global cluster pruning, which eliminates redundant clusters across all layers through a unified importance scoring mechanism that accounts for cross-layer homogeneity. We validate C-PRUNE through extensive experiments on multiple MoE models and benchmarks. The results demonstrate that C-PRUNE effectively reduces model size while outperforming existing MoE pruning methods. The effectiveness is observed across diverse domains, with notable performance in the medical field. We provide code. https://github.com/Fighoture/ MoE_unsupervised_pruning