Papers › CuMo: Scaling Multimodal LLM with Co-Upcycled Mixture-of-Experts

CuMo: Scaling Multimodal LLM with Co-Upcycled Mixture-of-Experts

9 May 2024arXiv:2405.05949archive 2025-07-28

Jiachen Li, Xinyao Wang, Sijie Zhu, Chia-Wen Kuo, Lu Xu, Fan Chen, Jitesh Jain, Humphrey Shi, Longyin Wen

Recent advancements in Multimodal Large Language Models (LLMs) have focused primarily on scaling by increasing text-image pair data and enhancing LLMs to improve performance on multimodal tasks. However, these scaling approaches are computationally expensive and overlook the significance of improving model capabilities from the vision side. Inspired by the successful applications of Mixture-of-Experts (MoE) in LLMs, which improves model scalability during training while keeping inference costs similar to those of smaller models, we propose CuMo. CuMo incorporates Co-upcycled Top-K sparsely-gated Mixture-of-experts blocks into both the vision encoder and the MLP connector, thereby enhancing the multimodal LLMs with minimal additional activated parameters during inference. CuMo first pre-trains the MLP blocks and then initializes each expert in the MoE block from the pre-trained MLP block during the visual instruction tuning stage. Auxiliary losses are used to ensure a balanced loading of experts. CuMo outperforms state-of-the-art multimodal LLMs across various VQA and visual-instruction-following benchmarks using models within each model size group, all while training exclusively on open-sourced datasets. The code and model weights for CuMo are open-sourced at https://github.com/SHI-Labs/CuMo.

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Tasks

Image CaptioningInstruction FollowingMixture-of-ExpertsVisual Question AnsweringVisual Question Answering (VQA)visual instruction following

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Visual Question Answering MM-Vet CuMo-7B GPT-4 score 51.0 #60 of 231 Archive leaderboard report
Visual Question Answering MM-Vet CuMo-7B Params 7B #60 of 231 Archive leaderboard report
Visual Question Answering MMBench CuMo-7B GPT-3.5 score 73.0 #2 of 5 Archive leaderboard report
Visual Question Answering (VQA) GQA test-dev CuMo-7B Accuracy 64.9 #3 of 17 Archive leaderboard report
Visual Question Answering (VQA) VQA v2 test-dev CuMo-7B Accuracy 82.2 #6 of 56 Archive leaderboard report
visual instruction following LLaVA-Bench CuMo-7B avg score 85.7 #1 of 8 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

MoE

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