# EC-DIT: Scaling Diffusion Transformers with Adaptive Expert-Choice Routing

arXiv: https://arxiv.org/abs/2410.02098 · HTML: https://mlsanity.com/paper/2410.02098/

## Key facts

- Cited by 30 papers in the map (data through 14 Oct 2026).
- Placed in Diffusion foundations and sampling, one of 14 directions in Diffusion models.
- Builds on 37 of its 46 references that are in the map.
- First posted on arXiv 2 Oct 2024.

## Placed in

- Diffusion models / [Diffusion foundations and sampling](https://mlsanity.com/diffusion/diffusion-foundations-and-sampling/)
- Mixture-of-experts / [Vision mixture-of-experts](https://mlsanity.com/moe/vision-mixture-of-experts/)

## Builds on (most cited first, 30 of 37)

- [Denoising Diffusion Probabilistic Models](https://mlsanity.com/paper/2006.11239/) (2020)
- [High-Resolution Image Synthesis with Latent Diffusion Models](https://mlsanity.com/paper/2112.10752/) (2021)
- [Microsoft COCO: Common Objects in Context](https://mlsanity.com/paper/1405.0312/) (2014)
- [Exploring the Limits of Transfer Learning with a Unified Text-to-Text Transformer](https://mlsanity.com/paper/1910.10683/) (2019)
- [Hierarchical Text-Conditional Image Generation with CLIP Latents](https://mlsanity.com/paper/2204.06125/) (2022)
- [Photorealistic Text-to-Image Diffusion Models with Deep Language Understanding](https://mlsanity.com/paper/2205.11487/) (2022)
- [Scalable Diffusion Models with Transformers](https://mlsanity.com/paper/2212.09748/) (2022)
- [Flow Matching for Generative Modeling](https://mlsanity.com/paper/2210.02747/) (2022)
- [Flow Straight and Fast: Learning to Generate and Transfer Data with Rectified Flow](https://mlsanity.com/paper/2209.03003/) (2022)
- [Outrageously Large Neural Networks: The Sparsely-Gated Mixture-of-Experts Layer](https://mlsanity.com/paper/1701.06538/) (2017)
- [Switch Transformers: Scaling to Trillion Parameter Models with Simple and Efficient Sparsity](https://mlsanity.com/paper/2101.03961/) (2021)
- [CLIPScore: A Reference-free Evaluation Metric for Image Captioning](https://mlsanity.com/paper/2104.08718/) (2021)
- [GShard: Scaling Giant Models with Conditional Computation and Automatic Sharding](https://mlsanity.com/paper/2006.16668/) (2020)
- [Scaling Autoregressive Models for Content-Rich Text-to-Image Generation](https://mlsanity.com/paper/2206.10789/) (2022)
- [GenEval: An Object-Focused Framework for Evaluating Text-to-Image Alignment](https://mlsanity.com/paper/2310.11513/) (2023)
- [eDiff-I: Text-to-Image Diffusion Models with an Ensemble of Expert Denoisers](https://mlsanity.com/paper/2211.01324/) (2022)
- [GLaM: Efficient Scaling of Language Models with Mixture-of-Experts](https://mlsanity.com/paper/2112.06905/) (2021)
- [PixArt-α: Fast Training of Diffusion Transformer for Photorealistic Text-to-Image Synthesis](https://mlsanity.com/paper/2310.00426/) (2023)
- [Mixture-of-Experts with Expert Choice Routing](https://mlsanity.com/paper/2202.09368/) (2022)
- [Make-A-Scene: Scene-Based Text-to-Image Generation with Human Priors](https://mlsanity.com/paper/2203.13131/) (2022)
- [Transfusion: Predict the Next Token and Diffuse Images with One Multi-Modal Model](https://mlsanity.com/paper/2408.11039/) (2024)
- [ST-MoE: Designing Stable and Transferable Sparse Expert Models](https://mlsanity.com/paper/2202.08906/) (2022)
- [From Sparse to Soft Mixtures of Experts](https://mlsanity.com/paper/2308.00951/) (2023)
- [MM1: Methods, Analysis & Insights from Multimodal LLM Pre-training](https://mlsanity.com/paper/2403.09611/) (2024)
- [Fast Training of Diffusion Models with Masked Transformers](https://mlsanity.com/paper/2306.09305/) (2023)
- [SparseCtrl: Adding Sparse Controls to Text-to-Video Diffusion Models](https://mlsanity.com/paper/2311.16933/) (2023)
- [Davidsonian Scene Graph: Improving Reliability in Fine-grained Evaluation for Text-to-Image Generation](https://mlsanity.com/paper/2310.18235/) (2023)
- [RAPHAEL: Text-to-Image Generation via Large Mixture of Diffusion Paths](https://mlsanity.com/paper/2305.18295/) (2023)
- [ERNIE-ViLG 2.0: Improving Text-to-Image Diffusion Model with Knowledge-Enhanced Mixture-of-Denoising-Experts](https://mlsanity.com/paper/2210.15257/) (2022)
- [Improving Image Captioning with Better Use of Captions](https://mlsanity.com/paper/2006.11807/) (2020)

## Built on by (most cited first, 30 of 30)

- [Routing Matters in MoE: Scaling Diffusion Transformers with Explicit Routing Guidance](https://mlsanity.com/paper/2510.24711/) (2025)
- [DiffMoE: Dynamic Token Selection for Scalable Diffusion Transformers](https://mlsanity.com/paper/2503.14487/) (2025)
- [TREAD: Token Routing for Efficient Architecture-agnostic Diffusion Training](https://mlsanity.com/paper/2501.04765/) (2025)
- [Instruction-Following Pruning for Large Language Models](https://mlsanity.com/paper/2501.02086/) (2025)
- [Scaling Properties of Diffusion Models for Perceptual Tasks](https://mlsanity.com/paper/2411.08034/) (2024)
- [Expert Race: A Flexible Routing Strategy for Scaling Diffusion Transformer with Mixture of Experts](https://mlsanity.com/paper/2503.16057/) (2025)
- [Scale-wise Distillation of Diffusion Models](https://mlsanity.com/paper/2503.16397/) (2025)
- [TimeStep Master: Asymmetrical Mixture of Timestep LoRA Experts for Versatile and Efficient Diffusion Models in Vision](https://mlsanity.com/paper/2503.07416/) (2025)
- [ERMoE: Eigen-Reparameterized Mixture-of-Experts for Stable Routing and Interpretable Specialization](https://mlsanity.com/paper/2511.10971/) (2025)
- [Efficient Training of Diffusion Mixture-of-Experts Models: A Practical Recipe](https://mlsanity.com/paper/2512.01252/) (2025)
- [Route Experts by Sequence, not by Token](https://mlsanity.com/paper/2511.06494/) (2025)
- [ALTER: All-in-One Layer Pruning and Temporal Expert Routing for Efficient Diffusion Generation](https://mlsanity.com/paper/2505.21817/) (2025)
- [Expert Threshold Routing for Autoregressive Language Modeling with Dynamic Computation Allocation and Load Balancing](https://mlsanity.com/paper/2603.11535/) (2026)
- [Expert-Choice Routing Enables Adaptive Computation in Diffusion Language Models](https://mlsanity.com/paper/2604.01622/) (2026)
- [LaTtE-Flow: Layerwise Timestep-Expert Flow-based Transformer](https://mlsanity.com/paper/2506.06952/) (2025)
- [InterMoE: Individual-Specific 3D Human Interaction Generation via Dynamic Temporal-Selective MoE](https://mlsanity.com/paper/2511.13488/) (2025)
- [Expert-Data Alignment Governs Generation Quality in Decentralized Diffusion Models](https://mlsanity.com/paper/2602.02685/) (2026)
- [Complete-muE: Optimal Hyperparameter Transfer and Scaling for MoE Models](https://mlsanity.com/paper/2605.23893/) (2026)
- [Focusing on What Matters: Saliency-Harnessing Accurate Routing for Diffusion MoE](https://mlsanity.com/paper/2606.26938/) (2026)
- [InstructMoLE: Instruction-Guided Mixture of Low-rank Experts for Multi-Conditional Image Generation](https://mlsanity.com/paper/2512.21788/) (2025)
- [From Agnostic to Specific: Latent Preference Diffusion for Multi-Behavior Sequential Recommendation](https://mlsanity.com/paper/2602.23132/) (2026)
- [CARE-Edit: Condition-Aware Routing of Experts for Contextual Image Editing](https://mlsanity.com/paper/2603.08589/) (2026)
- [FocusDiT: Masking Queries in Diffusion Transformers for Fine-grained Image Generation](https://mlsanity.com/paper/2606.02090/) (2026)
- [MoECa: Aligning Feature Reuse with Expert Decomposition in Diffusion Transformers](https://mlsanity.com/paper/2606.15615/) (2026)
- [MoECodec: Image Compression for joint human and machine perception via Mixture-of-Experts](https://mlsanity.com/paper/2606.21033/) (2026)
- [MMOE: Modernizing Diffusion Transformers with Efficient Expert Design](https://mlsanity.com/paper/2607.24665/) (2026)
- [SonicWeave: Chunk-Routed Mixture-of-Experts for Unified Audio Scene Generation](https://mlsanity.com/paper/2608.09571/) (2026)
- [SAGE: Subspace Alignment for Classifier-Free Guidance in Mixture-of-Experts Diffusion Models](https://mlsanity.com/paper/2609.34525/) (2026)
- [ITC-MoE: Importance-guided Token-aware Compression for MoE Diffusion Language Models](https://mlsanity.com/paper/2610.01296/) (2026)
- [PixelMoE: Scaling Pixel-Space Diffusion with LLM-Style Mixture-of-Experts](https://mlsanity.com/paper/2610.18857/) (2026)

## Abstract (arXiv)

Diffusion transformers have been widely adopted for text-to-image synthesis. While scaling these models up to billions of parameters shows promise, the effectiveness of scaling beyond current sizes remains underexplored and challenging. By explicitly exploiting the computational heterogeneity of image generations, we develop a new family of Mixture-of-Experts (MoE) models (EC-DIT) for diffusion transformers with expert-choice routing. EC-DIT learns to adaptively optimize the compute allocated to understand the input texts and generate the respective image patches, enabling heterogeneous computation aligned with varying text-image complexities. This heterogeneity provides an efficient way of scaling EC-DIT up to 97 billion parameters and achieving significant improvements in training convergence, text-to-image alignment, and overall generation quality over dense models and conventional MoE models. Through extensive ablations, we show that EC-DIT demonstrates superior scalability and adaptive compute allocation by recognizing varying textual importance through end-to-end training. Notably, in text-to-image alignment evaluation, our largest models achieve a state-of-the-art GenEval score of 71.68% and still maintain competitive inference speed with intuitive interpretability.