# ReMoE: Fully Differentiable Mixture-of-Experts with ReLU Routing

arXiv: https://arxiv.org/abs/2412.14711 · HTML: https://mlsanity.com/paper/2412.14711/

## Key facts

- Cited by 54 papers in the map (data through 14 Oct 2026).
- Placed in Expert routing strategies, one of 12 directions in Mixture-of-experts.
- Builds on 57 of its 63 references that are in the map.
- First posted on arXiv 19 Dec 2024.

## Placed in

- Mixture-of-experts / [Expert routing strategies](https://mlsanity.com/moe/expert-routing-strategies/)

## Builds on (most cited first, 30 of 57)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [LLaMA: Open and Efficient Foundation Language Models](https://mlsanity.com/paper/2302.13971/) (2023)
- [Scaling Laws for Neural Language Models](https://mlsanity.com/paper/2001.08361/) (2020)
- [Think you have Solved Question Answering? Try ARC, the AI2 Reasoning Challenge](https://mlsanity.com/paper/1803.05457/) (2018)
- [Mamba: Linear-Time Sequence Modeling with Selective State Spaces](https://mlsanity.com/paper/2312.00752/) (2023)
- [RoFormer: Enhanced Transformer with Rotary Position Embedding](https://mlsanity.com/paper/2104.09864/) (2021)
- [HellaSwag: Can a Machine Really Finish Your Sentence?](https://mlsanity.com/paper/1905.07830/) (2019)
- [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)
- [Neural Machine Translation of Rare Words with Subword Units](https://mlsanity.com/paper/1508.07909/) (2015)
- [PIQA: Reasoning about Physical Commonsense in Natural Language](https://mlsanity.com/paper/1911.11641/) (2019)
- [The Pile: An 800GB Dataset of Diverse Text for Language Modeling](https://mlsanity.com/paper/2101.00027/) (2020)
- [BoolQ: Exploring the Surprising Difficulty of Natural Yes/No Questions](https://mlsanity.com/paper/1905.10044/) (2019)
- [Estimating or Propagating Gradients Through Stochastic Neurons for Conditional Computation](https://mlsanity.com/paper/1308.3432/) (2013)
- [Megatron-LM: Training Multi-Billion Parameter Language Models Using Model Parallelism](https://mlsanity.com/paper/1909.08053/) (2019)
- [Mixtral of Experts](https://mlsanity.com/paper/2401.04088/) (2024)
- [GLU Variants Improve Transformer](https://mlsanity.com/paper/2002.05202/) (2020)
- [GShard: Scaling Giant Models with Conditional Computation and Automatic Sharding](https://mlsanity.com/paper/2006.16668/) (2020)
- [Root Mean Square Layer Normalization](https://mlsanity.com/paper/1910.07467/) (2019)
- [GQA: Training Generalized Multi-Query Transformer Models from Multi-Head Checkpoints](https://mlsanity.com/paper/2305.13245/) (2023)
- [ZeRO: Memory Optimizations Toward Training Trillion Parameter Models](https://mlsanity.com/paper/1910.02054/) (2019)
- [The LAMBADA dataset: Word prediction requiring a broad discourse context](https://mlsanity.com/paper/1606.06031/) (2016)
- [DeepSeekMoE: Towards Ultimate Expert Specialization in Mixture-of-Experts Language Models](https://mlsanity.com/paper/2401.06066/) (2024)
- [RACE: Large-scale ReAding Comprehension Dataset From Examinations](https://mlsanity.com/paper/1704.04683/) (2017)
- [Efficient Large-Scale Language Model Training on GPU Clusters Using Megatron-LM](https://mlsanity.com/paper/2104.04473/) (2021)
- [Mixture-of-Experts with Expert Choice Routing](https://mlsanity.com/paper/2202.09368/) (2022)
- [Retentive Network: A Successor to Transformer for Large Language Models](https://mlsanity.com/paper/2307.08621/) (2023)
- [ST-MoE: Designing Stable and Transferable Sparse Expert Models](https://mlsanity.com/paper/2202.08906/) (2022)
- [MInference 1.0: Accelerating Pre-filling for Long-Context LLMs via Dynamic Sparse Attention](https://mlsanity.com/paper/2407.02490/) (2024)
- [BASE Layers: Simplifying Training of Large, Sparse Models](https://mlsanity.com/paper/2103.16716/) (2021)

## Built on by (most cited first, 30 of 54)

- [Expert Race: A Flexible Routing Strategy for Scaling Diffusion Transformer with Mixture of Experts](https://mlsanity.com/paper/2503.16057/) (2025)
- [PVChat: Personalized Video Chat with One-Shot Learning](https://mlsanity.com/paper/2503.17069/) (2025)
- [LD-MoLE: Learnable Dynamic Routing for Mixture of LoRA Experts](https://mlsanity.com/paper/2509.25684/) (2025)
- [Elastic MoE: Unlocking the Inference-Time Scalability of Mixture-of-Experts](https://mlsanity.com/paper/2509.21892/) (2025)
- [Dense Backpropagation Improves Training for Sparse Mixture-of-Experts](https://mlsanity.com/paper/2504.12463/) (2025)
- [Learning to Skip the Middle Layers of Transformers](https://mlsanity.com/paper/2506.21103/) (2025)
- [HiMoE-VLA: Hierarchical Mixture-of-Experts for Generalist Vision-Language-Action Policies](https://mlsanity.com/paper/2512.05693/) (2025)
- [Grove MoE: Towards Efficient and Superior MoE LLMs with Adjugate Experts](https://mlsanity.com/paper/2508.07785/) (2025)
- [When Are Experts Misrouted? Counterfactual Routing Analysis in Mixture-of-Experts Language Models](https://mlsanity.com/paper/2605.07260/) (2026)
- [Analytical FFN-to-MoE Restructuring via Activation Pattern Analysis](https://mlsanity.com/paper/2502.04416/) (2025)
- [BlockFFN: Towards End-Side Acceleration-Friendly Mixture-of-Experts with Chunk-Level Activation Sparsity](https://mlsanity.com/paper/2507.08771/) (2025)
- [Understanding the Mixture-of-Experts with Nadaraya-Watson Kernel](https://mlsanity.com/paper/2509.25913/) (2025)
- [Towards Stable and Effective Reinforcement Learning for Mixture-of-Experts](https://mlsanity.com/paper/2510.23027/) (2025)
- [Route Experts by Sequence, not by Token](https://mlsanity.com/paper/2511.06494/) (2025)
- [Spark Transformer: Reactivating Sparsity in FFN and Attention](https://mlsanity.com/paper/2506.06644/) (2025)
- [Synergistic Intra- and Cross-Layer Regularization Losses for MoE Expert Specialization](https://mlsanity.com/paper/2602.14159/) (2026)
- [Grouter: Decoupling Routing from Representation for Accelerated MoE Training](https://mlsanity.com/paper/2603.06626/) (2026)
- [φ-Balancing for Mixture-of-Experts Training](https://mlsanity.com/paper/2605.15403/) (2026)
- [Robust Experts: the Effect of Adversarial Training on CNNs with Sparse Mixture-of-Experts Layers](https://mlsanity.com/paper/2509.05086/) (2025)
- [Tying the Loop -- Tied Expert Layers in Mixture-of-Experts Language Models](https://mlsanity.com/paper/2606.16825/) (2026)
- [Rethinking Gating Mechanism in Sparse MoE: Handling Arbitrary Modality Inputs with Confidence-Guided Gate](https://mlsanity.com/paper/2505.19525/) (2025)
- [Maximum Score Routing For Mixture-of-Experts](https://mlsanity.com/paper/2508.12801/) (2025)
- [Alleviating Forgetfulness of Linear Attention by Hybrid Sparse Attention and Contextualized Learnable Token Eviction](https://mlsanity.com/paper/2510.20787/) (2025)
- [DTop-p MoE: Sparsity-Controlled Dynamic Top-p MoE for Foundation Model Pre-training](https://mlsanity.com/paper/2512.13996/) (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)
- [Geometric Regularization in Mixture-of-Experts: The Disconnect Between Weights and Activations](https://mlsanity.com/paper/2601.00457/) (2026)
- [Multi-Head LatentMoE and Head Parallel: Communication-Efficient and Deterministic MoE Parallelism](https://mlsanity.com/paper/2602.04870/) (2026)
- [Routing Absorption in Sparse Attention: Why Random Gates Are Hard to Beat](https://mlsanity.com/paper/2603.02227/) (2026)
- [A Deep Generative Approach to Stratified Learning](https://mlsanity.com/paper/2604.10650/) (2026)

## Abstract (arXiv)

Sparsely activated Mixture-of-Experts (MoE) models are widely adopted to scale up model capacity without increasing the computation budget. However, vanilla TopK routers are trained in a discontinuous, non-differentiable way, limiting their performance and scalability. To address this issue, we propose ReMoE, a fully differentiable MoE architecture that offers a simple yet effective drop-in replacement for the conventional TopK+Softmax routing, utilizing ReLU as the router instead. We further propose methods to regulate the router's sparsity while balancing the load among experts. ReMoE's continuous nature enables efficient dynamic allocation of computation across tokens and layers, while also exhibiting domain specialization. Our experiments demonstrate that ReMoE consistently outperforms vanilla TopK-routed MoE across various model sizes, expert counts, and levels of granularity. Furthermore, ReMoE exhibits superior scalability with respect to the number of experts, surpassing traditional MoE architectures. The implementation based on Megatron-LM is available at https://github.com/thu-ml/ReMoE.
