Expert Race: A Flexible Routing Strategy for Scaling Diffusion
  Transformer with Mixture of Experts
Authors: name: Yike Yuan; name: Ziyu Wang; name: Zihao Huang; name: Defa Zhu; name: Xun Zhou; name: Jingyi Yu; name: Qiyang Min
Published: 2025-03-20 11:45:08

Abstract: Diffusion models have emerged as mainstream framework in visual generation.
Building upon this success, the integration of Mixture of Experts (MoE) methods
has shown promise in enhancing model scalability and performance. In this
paper, we introduce Race-DiT, a novel MoE model for diffusion transformers with
a flexible routing strategy, Expert Race. By allowing tokens and experts to
compete together and select the top candidates, the model learns to dynamically
assign experts to critical tokens. Additionally, we propose per-layer
regularization to address challenges in shallow layer learning, and router
similarity loss to prevent mode collapse, ensuring better expert utilization.
Extensive experiments on ImageNet validate the effectiveness of our approach,
showcasing significant performance gains while promising scaling properties.