arXiv Machine Learning

Denoising Blocks, Not Tokens: Efficient Compressed Continuous Diffusion with Branching Token Realization

arXiv Machine Learning
Sep 16

Window-Diffusion: Accelerating Diffusion Language Model Inference with Windowed Token Pruning and Caching

The paper introduces Window-Diffusion, a method that accelerates diffusion language model inference by pruning and caching tokens within a sliding window. It categorizes undecoded tokens into active, buffer, and far-field groups, computing only the first two while discarding the rest. Experiments on LLaDA and Dream demonstrate up to 99× speedup with minimal loss in generation quality.

By Fengrui Zuo, Zhiwei Ke, Yiming Liu, Wenqi Lou, Chao Wang, Xuehai Zhou
arXiv AI
Oct 9

DynaTE: Accelerating Diffusion LLMs via Dynamic Token Execution

DynaTE is a hardware–software co‑design that accelerates diffusion‑based large language models (dLLMs) by dynamically adapting execution to token states. It skips low‑utility token computations, uses a dimension‑reconfigurable processing array, refines locally dependent tokens with FLDD, and streams vocabulary to handle irregular token patterns. These techniques yield 2.05–2.78× speedup and 2.99–3.93× higher energy efficiency compared to existing dLLM accelerators, and outperform Jetson AGX Orin by 2.55× speedup and 6.07× energy efficiency.

By Minghan Jiang, Jiayi Wang, Shuaiting Li, Haibin Shen, Kejie Huang
arXiv Machine Learning
Oct 12

Rethinking the Roles of Diffusion and Decoding: Predictive-State Flows for Parallel Language Generation

The paper proposes Predictive-State Flows (PSF), a new architecture for continuous diffusion language models that separates the diffusion prior’s role to generate high‑level predictive states and the decoder’s role to resolve token‑level choices. PSF partitions sequences into blocks, uses a rectified‑flow prior to produce predictive states, and then a block‑causal decoder generates all blocks in parallel, reducing token‑level sequential depth. Experiments on OpenWebText show that a 197M‑parameter PSF model with eight predictive states achieves a generative perplexity of 22.8 and a MAUVE@512 of 0.93 while using far fewer FLOPs than a comparable ELF‑B model.

By Jinjin He, Xinsong Feng, Lucheng Fu, Sinan Wang, Bo Zhu, Jiayun Wang
arXiv Computation and Language
Aug 25

Accelerating Diffusion Language Models via Structured Suffix Modeling

The paper introduces a training‑free structured suffix modeling technique to accelerate Diffusion Language Models (DLMs). It partitions the suffix into local, middle, and tail regions, retaining varying numbers of tokens per region and incorporating previous decoding results into current token representations. Experiments on three DLMs show significant speedups—up to 72.81× in long‑sequence inference—while often improving performance, and the method is compatible with existing acceleration strategies.

By Zifeng Cheng, Keda Li, Zhiwei Jiang, Cong Wang, Fei Shen, Qing Gu
arXiv Machine Learning
Sep 4

Unlocking Lossless Speedups in LLMs via Discrete Diffusion

arXiv:2609. 04010v1 Announce Type: new Abstract: Large Language Models (LLMs) owe much of their success to next-token prediction (NTP), but their autoregressive (AR) structure requires slow, sequential token generation.

By Subham Sekhar Sahoo, Lingjie Chen, Khiem Pham, Jonathan Geuter, Chaitanya Dwivedi, Varad Pimpalkhute, Yash Akhauri, Alexander Moreno, Mikhail Yurochkin, Zhenting Wang, Mostafa Elhoushi, Nolan Dey, Shane Bergsma, Joel Hestness, John Thickstun, Eric Xing, Zhengzhong Liu
arXiv Machine Learning
Sep 18

Block Parallelism For Efficient Distributed Long-Context Diffusion Language Model Training

The paper introduces Block Parallelism (BP) and Context‑Sharded Block Parallelism (CSBP) to improve training efficiency for Block Diffusion Language Models (BDLMs) with long contexts. By assigning each corrupted‑block computation to a separate rank and sharding the shared clean sequence, CSBP reduces communication overhead and memory usage while preserving training semantics. Experiments on 16 H200 GPUs and 8 H100 GPUs show throughput gains of up to 1.61× and 7.59×, respectively, and higher benchmark pass rates in practical fine‑tuning scenarios.

By Tarun Suresh, Pranshu Chaturvedi, Hangoo Kang, Parth Shroff, Ishan S. Khare, Hermann Kumbong, Azalia Mirhoseini
arXiv Computation and Language
Sep 23

Flash-dLLM: IO-Aware KV Caching and Parallel Decoding for Fast, Memory-Efficient Diffusion LLMs

Flash-dLLM is a training‑free inference acceleration framework that improves the speed and memory efficiency of Diffusion Large Language Models (dLLMs). It tackles GPU memory I/O bottlenecks by introducing an I/O‑aware fused KV‑cache kernel and then employs a draft‑and‑verify decoding strategy that uses the dLLM itself as both drafter and verifier. Experiments on mathematical reasoning and code‑generation tasks show Flash‑dLLM outperforms existing acceleration methods, achieving up to 11.0× speedups over the Elastic‑Cache baseline.

By Quan Nguyen-Tri, Mukul Ranjan, Zhiqiang Shen
arXiv Machine Learning
Sep 14

Fixed State, Long Reach: What a Constant-Size Cache Buys Block Diffusion at Scale

The paper investigates how block‑diffusion language models can use a constant‑size cache to enable efficient parallel decoding. By employing sequence mixers that summarize completed blocks into a reusable state and a block‑causal training objective, the authors pretrain three 3B block‑diffusion denoisers (attention, Mamba, and hybrid) on 300 B tokens. The resulting state‑space cache remains O(1) in memory and latency regardless of context length, yielding significant speed‑up and memory savings compared to traditional attention‑based caches, especially at very long sequences.

By Vaibhav Singh, Pierre-Andr\'e No\"el, Torsten Scholak, Eugene Belilovsky, Oleksiy Ostapenko
arXiv Machine Learning
Jun 26

Dynamic-dLLM: Dynamic Cache-Budget and Adaptive Parallel Decoding for Training-Free Acceleration of Diffusion LLM

arXiv:2606. 26120v1 Announce Type: cross Abstract: Diffusion Large Language Models (dLLMs) offer a promising alternative to autoregressive models, excelling in text generation tasks due to their bidirectional attention mechanisms.

By Tianyi Wu, Xiaoxi Sun, Yanhua Jiao, Yulin Li, Yixin Chen, YunHao Cao, YiQi Hu, Zhuotao Tian