Orthrus is a hybrid autoregressive‑diffusion model that claims to perform lossless speculative decoding by generating multiple tokens in parallel while maintaining a frozen autoregressive backbone. In our independent reproduction, we found that under BF16 precision the model matches the exact autoregressive trajectory only about 45% of the time, whereas with FP32 precision it achieves perfect matching on all evaluated prompts. Despite trajectory mismatches at lower precision, Orthrus does not exhibit systematic degradation on downstream lm‑eval‑harness benchmarks.
By Ilya Koziev, Leonid Sinev, Ivan Oseledets
arXiv:2606. 27474v1 Announce Type: cross Abstract: How should we evaluate generation systems that combine autoregressive (AR) and diffusion decoding?
By Aditi Gupta, Neel Mishra, Kushagra Trivedi, Pawan Kumar
arXiv:2608. 08721v1 Announce Type: cross Abstract: Speculative decoding accelerates large language model inference by drafting multiple tokens for parallel verification, with efficiency critically determined by the speculative length selected at each decoding round.
By Zexun Lin, Yuan Feng, Junlin Lv, Kevin S. Zhou, Xike Xie
ResiSpec is a framework that improves speculative decoding for large language models by reshaping the residual distribution during verification. It addresses the problem of residual drift, where rejected candidates cause the target distribution to diverge from the draft model’s predictions, rendering later candidates ineffective. By aligning the verification process with the draft model’s high‑confidence regions, ResiSpec prevents candidate obsolescence and achieves up to 1.92× speedup over existing multi‑candidate methods.
By Zhi-Kai Chen, Jun-Jie Tao, Wei-Xiang Mao, De-Chuan Zhan, Han-Jia Ye
The paper introduces TSS, a target-side sparsification framework that selectively skips layers in a target verifier during speculative decoding for domain-specific large language models. By exploring multi-layer skip configurations with an acceptance- and metric-aware breadth search, TSS reduces verification cost, increases draft acceptance, and can even improve downstream task performance without retraining. Experiments on Spec-Bench demonstrate consistent gains across domains and model scales, notably boosting translation throughput by 1.68× and improving BLEU scores significantly.
By Haibo Hu, Lianming Huang, Qiao Li, Nan Guan, Chun Jason Xue
The paper introduces a trajectory-level speculative decoding framework for diffusion-based language models (dLLMs), addressing the limitation of existing strategies that revert to single-token generation when confidence is low. By constructing draft denoising trajectories through confidence-stratified tree exploration and verifying them with blockwise parallel evaluation and bidirectional attention masking, the method also incorporates inter-block speculation to exploit the models’ bidirectional structure. Experiments show a 30–40% reduction in denoising iterations, a token-per-step increase from 2.6 to 4.3, and a 7–14× speedup over vanilla dLLMs while maintaining accuracy within 1% on reasoning and code benchmarks.
By Tianxiang Pan, Baitao Gong, Mo Guang, Hongwei Yong, Tianpeng Jiang, Yaqian Li, Zheng Cao, Kaiwen Long
The paper demonstrates that greedy decoding from large language models is not precision‑invariant: the same model, prompt, and decoding algorithm can produce different outputs when run in BF16 versus FP16 on identical hardware. Across six models (1.1B–7B parameters, four families, and 12B) and three benchmarks, 49–100 % of prompts diverge, with a single token flip often cascading into trajectory‑level divergence. The authors develop an empirical error‑propagation analysis that identifies the top‑two logit margin at the LM head as the key factor, and they propose a low‑overhead intervention—selective FP32 LM head recomputation—that improves exact agreement by 22–36 percentage points with less than 4 % latency overhead.
"whyItMatters":"The findings reveal that precision choices can fundamentally alter model outputs, challenging the assumption of deterministic greedy decoding and highlighting the need for precision‑aware inference strategies."
By Gaoyuan Du, Anam Nawaz Khan, Rex Zhou, Xiaoyang Liu, Deepayan Chakrabarti, Fnu Suya, Xueping Li
arXiv:2609.36590v1 Announce Type: cross
Abstract: Self-speculative decoding accelerates large language model (LLM) inference by drafting tokens from the target model itself, but faces a sharp tradeof...
By Hankun Lin, Patrick Pynadath, Ruqi Zhang
arXiv:2607. 05147v1 Announce Type: new Abstract: Speculative decoding accelerates Large Language Model (LLM) inference by decoupling draft generation from target verification.
By Xin Cheng, Xingkai Yu, Chenze Shao, Jiashi Li, Yunfan Xiong, Yi Qian, Jiaqi Zhu, Shirong Ma, Xiaokang Zhang, Jiasheng Ye, Qinyu Chen, Chengqi Deng, Jiping Yu, Damai Dai, Zhengyan Zhang, Yixuan Wei, Yixuan Tan, Wenkai Yang, Runxin Xu, Yu Wu, Zhean Xu, Xuanyu Wang, Muyang Chen, Rui Tian, Xiao Bi, Zhewen Hao, Shaoyuan Chen, Huanqi Cao, Wentao Zhang, Anyi Xu, Huishuai Zhang, Dongyan Zhao, Wenfeng Liang
arXiv:2609.37029v1 Announce Type: cross
Abstract: Speculative decoding accelerates autoregressive inference by verifying multiple draft tokens in a single target forward pass. However, as the context...
By Hao-Yuan He, Peng-Fei Liu, Si Shen, Ming Li
arXiv:2606. 02544v1 Announce Type: cross Abstract: Diffusion large language models (dLLMs) have recently emerged as a promising alternative to autoregressive (AR) LLMs, offering faster inference through parallel or blockwise decoding.
By Junxia Cui, Haotian Ye, Runchu Tian, Hongcan Guo, Jinya Jiang, Haoru Li, Chaojie Ren, Yiming Huang, Kaijie Zhu, Zhongkai Yu, Kun Zhou, Jingbo Shang
The paper examines lossy verification techniques used in speculative decoding for large language models, showing that many methods can be grouped into truncation-based and collaborative verification categories. It analyzes how these approaches alter the decoding distribution, revealing that truncation-based methods can significantly degrade performance due to distributional distortion, while collaborative methods depend more on overshoot suppression and supervision quality than on simple interpolation between draft and target models. A diagnostic evaluation framework is introduced to assess these failure modes across curated benchmarks.
By Tianyu Wang, Yuxuan Zhou, Heng Li, Wenbin Wang, Zikai Xiao, Chunrui Zheng, Junyuan Shang