Understanding and Accelerating the Training of Masked Diffusion Language Models
On the map: Diffusion models → Discrete and text diffusion
Abstract (arXiv)
Masked diffusion models (MDMs) have emerged as a promising alternative to autoregressive models (ARMs) for language modeling. However, MDMs are known to learn substantially more slowly than ARMs, which may become problematic when scaling MDMs to larger models. Therefore, we ask the following question: how can we accelerate standard MDM training while maintaining its final performance? To this end, we first provide a detailed analysis of why MDM training is slow. We find that the main factor is the locality bias of language: the predictive information for a token is concentrated in nearby positions. We further investigate how this bias slows learning and suggest a simple yet effective remedy: bell-shaped time sampling as a training strategy. Notably, MDMs trained with our training recipe reach the same validation negative log-likelihood (NLL) up to ~4× faster than standard training on One Billion Word Benchmark (LM1B). We also show faster improvements in generative perplexity, zero-shot perplexity, and downstream task performance on various benchmarks.
Key facts. No citing papers in the map yet (data through 7 Oct 2026). Placed in Discrete and text diffusion, one of 14 directions in Diffusion models. Builds on 67 of its 76 references that are in the map. First posted on arXiv 13 May 2026.
Builds on
67 of 76 references.
Closest ancestors · 35
Same direction, newest first
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- 2022DiffusionBERT: Improving Generative Masked Language Models with Diffusion Models28 Nov
Other references · 32
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- 2023Judging LLM-as-a-Judge with MT-Bench and Chatbot Arenacited by 8,393
- 2022Scalable Diffusion Models with Transformerscited by 5,931
- 2021RoFormer: Enhanced Transformer with Rotary Position Embeddingcited by 4,581
- 2024GPT-4o System Cardcited by 4,467
- 2024Scaling Rectified Flow Transformers for High-Resolution Image Synthesiscited by 4,094
- 2019HellaSwag: Can a Machine Really Finish Your Sentence?cited by 4,018
- 2021Improved Denoising Diffusion Probabilistic Modelscited by 3,736
- 2022Elucidating the Design Space of Diffusion-Based Generative Modelscited by 2,994
- 2016Pointer Sentinel Mixture Modelscited by 2,992
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- 2019PIQA: Reasoning about Physical Commonsense in Natural Languagecited by 2,818
- 2015Character-level Convolutional Networks for Text Classificationcited by 2,293
- 2018Can a Suit of Armor Conduct Electricity? A New Dataset for Open Book Question Answeringcited by 2,114
- 2021Structured Denoising Diffusion Models in Discrete State-Spacescited by 1,665
- 2021Multitask Prompted Training Enables Zero-Shot Task Generalizationcited by 1,462
- 2024Qwen2.5-Coder Technical Reportcited by 1,151
- 2021Variational Diffusion Modelscited by 1,145
- 2016The LAMBADA dataset: Word prediction requiring a broad discourse contextcited by 960
- 2021Argmax Flows and Multinomial Diffusion: Learning Categorical Distributionscited by 566
- 2018A Discourse-Aware Attention Model for Abstractive Summarization of Long Documentscited by 477
- 2016A Corpus and Evaluation Framework for Deeper Understanding of Commonsense Storiescited by 413
- 2013One Billion Word Benchmark for Measuring Progress in Statistical Language Modelingcited by 302
- 2022Perception Prioritized Training of Diffusion Modelscited by 301
- 2025d1: Scaling Reasoning in Diffusion Large Language Models via Reinforcement Learningcited by 178
- 2024Distillation of Discrete Diffusion through Dimensional Correlationscited by 46
- 2024Improved Noise Schedule for Diffusion Trainingcited by 38
- 2024Evaluating the design space of diffusion-based generative modelscited by 25
- 2025Variational Autoencoding Discrete Diffusion with Enhanced Dimensional Correlations Modelingcited by 14
- 2026Stable-DiffCoder: Pushing the Frontier of Code Diffusion Large Language Modelcited by 12
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