ModularMoE: Fast LLM Customization with Parameter-Sharing Mixture-of-Experts for Low-Resource Settings
Paper · 2026 · Jiaxing Liu, Qi Qi, Haifeng Sun et al.
Summary
Running large language models on modest hardware is costly. Current customization routes either compress and fine-tune separately for every target task, which is expensive, or tune once on general data, which tends to hurt task-level quality through interference and forgetting. ModularMoE addresses this by turning an existing dense LLM into a compact Mixture-of-Experts in which experts share parameters. The authors record how neurons in the feed-forward layers fire together across many tasks and build a co-activation graph. They then cut that graph into equal-sized, non-overlapping modules. Each task-specific expert is a sparse selection of these modules, chosen by a differentiable DSelect-k router. A final multi-task fine-tuning stage makes the experts more specialized. At matched sparsity, the method beats strong baselines by 4.10% to 28.75% on average. On edge devices it runs up to 2.71× faster. This suggests specialized, lightweight models can be derived quickly from one shared modular model, which is useful for low-resource deployment.
Key points
- Pipeline: The method has three stages: module partitioning, expert construction, and multi-task fine-tuning.
- Partitioning applies the Karypis & Kumar graph partitioning algorithm to a neuron co-activation graph.
- Experts are built with DSelect-k instead of Top-k routing, since Top-k is less smooth and would change the FFN's original behavior.
- Fine-tuning cost: A masking-based MoE computation speeds up multi-task fine-tuning by 5.26×. On ReLU-LLaMA2-7B it trains in 1.77 h, versus 9.31 h for LoRA and 5.23 h for QLoRA, with only slightly lower scores.
- Hardware tests: Using llama.cpp, 4-bit quantized models were deployed on two edge platforms, a Raspberry Pi 4B and an NVIDIA Jetson TX2. Measured speedups were:
- 1.53× at 25% sparsity
- 2.15× at 50% sparsity
- 2.35× at 75% sparsity
- 2.71× at 87.5% sparsity
- Evaluation tasks: These include ARC-e, ARC-c, PIQA, ReCoRD and RACE, with experiments on LLaMA2-7B-based models.
- Limitations:
- Only two models were tested.
- Experts within one experiment had identical sizes.
- Experts defined by language, topic, or modality are left for future work.
Institutions
Fields, topics and concepts
📚 Shelves 5The field of science this work belongs to (OpenAlex fields).Computer Science · 16,667 worksArtificial Intelligence · 16,194 worksArts and Humanities · 16,039 worksLanguage and Linguistics · 15,891 worksComputer Vision and Pattern Recognition · 2,869 works
🧭 Topics 2Research subjects and languages the work is about.Language models & pretraining · 3,320 worksLow-resource languages · 267 works
Cite
Cite as Jiaxing Liu, Qi Qi, Haifeng Sun, Dunjun Li, Zirui Zhuang, Bo He, Xiang Yang, Cong Liu, Jianxin Liao and Jingyu Wang. 2026. ModularMoE: Fast LLM Customization with Parameter-Sharing Mixture-of-Experts for Low-Resource Settings. Findings of the Association for Computational Linguistics: ACL 2026.
@inproceedings{liu2026modularmoe,
title = {{ModularMoE: Fast LLM Customization with Parameter-Sharing Mixture-of-Experts for Low-Resource Settings}},
author = {Jiaxing Liu, Qi Qi, Haifeng Sun, Dunjun Li, Zirui Zhuang, Bo He, Xiang Yang, Cong Liu, Jianxin Liao and Jingyu Wang},
booktitle = {Findings of the Association for Computational Linguistics: ACL 2026},
year = {2026},
doi = {10.18653/v1/2026.findings-acl.174},
url = {https://doi.org/10.18653/v1/2026.findings-acl.174}
}References
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