MoE-Hub: Taming Software Complexity for Seamless MoE Overlap with Hardware-Accelerated Communication on Multi-GPU Systems

Zhuoshan Zhou; Chen Zhang; Shuyi Zhang; Qijun Zhang; Haibo Wang; Zhe Zhou; Zhipeng Tu; Guangyu Sun; Yijia Diao; Zhigang Ji; Jingwen Leng; Guanghui He; Minyi Guo

arXiv · 2605.05888

MoE-Hub: Taming Software Complexity for Seamless MoE Overlap with Hardware-Accelerated Communication on Multi-GPU Systems

Zhuoshan Zhou·Chen Zhang·Shuyi Zhang·Qijun Zhang·Haibo Wang·Zhe Zhou·Zhipeng Tu·Guangyu Sun·Yijia Diao·Zhigang Ji·Jingwen Leng·Guanghui He·Minyi Guo

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Abstract

The Mixture-of-Experts (MoE) architecture is crucial for scaling large language models, but its scalability is severely limited by inter-GPU communication bottlenecks in multi-GPU systems. Although overlapping communication with computation is a widely recognized optimization, its effective deployment still remains challenging, both in terms of performance and programmability. In this work, we identify the root cause as a fundamental abstraction mismatch between MoE's dynamic, irregular token-to-expert mapping and the static, address-centric communication model of modern GPUs, which necessitates a complex software mediation phase to resolve addresses before data transfers, limiting performance and software flexibility. To resolve this, we propose MoE-Hub, a hardware-software co-design that introduces a destination-agnostic communication paradigm. MoE-Hub decouples data transmission from address management, allowing producers to send data immediately after routing using only a logical destination, while address allocation and data-flow orchestration are handled transparently by lightweight hardware in the GPU hub. By hardware-accelerating the entire communication control plane, MoE-Hub enables seamless and transparent overlap. Our evaluation shows that MoE-Hub achieves 1.40x-3.08x per-layer and 1.21x-1.98x end-to-end speedup over state-of-the-art systems.

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Zhuoshan Zhou, Chen Zhang, Shuyi Zhang, Qijun Zhang, Haibo Wang, Zhe Zhou, Zhipeng Tu, Guangyu Sun, Yijia Diao, Zhigang Ji, Jingwen Leng, Guanghui He, Minyi Guo. 2026-05-07. MoE-Hub: Taming Software Complexity for Seamless MoE Overlap with Hardware-Accelerated Communication on Multi-GPU Systems. https://arxiv.org/abs/2605.05888

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