# DySpec: Faster Speculative Decoding with Dynamic Token Tree Structure

arXiv: https://arxiv.org/abs/2410.11744 · HTML: https://mlsanity.com/paper/2410.11744/

## Key facts

- Cited by 25 papers in the map (data through 14 Oct 2026).
- Placed in Speculative decoding, one of 12 directions in Efficient LLM inference and serving.
- Builds on 15 of its 26 references that are in the map.
- First posted on arXiv 15 Oct 2024.

## Placed in

- Efficient LLM inference and serving / [Speculative decoding](https://mlsanity.com/inference/speculative-decoding/)

## Builds on (most cited first, 15 of 15)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [Exploring the Limits of Transfer Learning with a Unified Text-to-Text Transformer](https://mlsanity.com/paper/1910.10683/) (2019)
- [Llama 2: Open Foundation and Fine-Tuned Chat Models](https://mlsanity.com/paper/2307.09288/) (2023)
- [Fast Inference from Transformers via Speculative Decoding](https://mlsanity.com/paper/2211.17192/) (2022)
- [Accelerating Large Language Model Decoding with Speculative Sampling](https://mlsanity.com/paper/2302.01318/) (2023)
- [Medusa: Simple LLM Inference Acceleration Framework with Multiple Decoding Heads](https://mlsanity.com/paper/2401.10774/) (2024)
- [Abstractive Text Summarization Using Sequence-to-Sequence RNNs and Beyond](https://mlsanity.com/paper/1602.06023/) (2016)
- [EAGLE-2: Faster Inference of Language Models with Dynamic Draft Trees](https://mlsanity.com/paper/2406.16858/) (2024)
- [SpecInfer: Accelerating Generative Large Language Model Serving with Tree-based Speculative Inference and Verification](https://mlsanity.com/paper/2305.09781/) (2023)
- [K-BERT: Enabling Language Representation with Knowledge Graph](https://mlsanity.com/paper/1909.07606/) (2019)
- [REST: Retrieval-Based Speculative Decoding](https://mlsanity.com/paper/2311.08252/) (2023)
- [SpecTr: Fast Speculative Decoding via Optimal Transport](https://mlsanity.com/paper/2310.15141/) (2023)
- [Sequoia: Scalable, Robust, and Hardware-aware Speculative Decoding](https://mlsanity.com/paper/2402.12374/) (2024)
- [Recurrent Drafter for Fast Speculative Decoding in Large Language Models](https://mlsanity.com/paper/2403.09919/) (2024)
- [Dynamic Depth Decoding: Faster Speculative Decoding for LLMs](https://mlsanity.com/paper/2409.00142/) (2024)

## Built on by (most cited first, 25 of 25)

- [A Survey on Parallel Text Generation: From Parallel Decoding to Diffusion Language Models](https://mlsanity.com/paper/2508.08712/) (2025)
- [Chain-of-Reasoning: Towards Unified Mathematical Reasoning in Large Language Models via a Multi-Paradigm Perspective](https://mlsanity.com/paper/2501.11110/) (2025)
- [Accelerating Speculative Decoding with Block Diffusion Draft Trees](https://mlsanity.com/paper/2604.12989/) (2026)
- [SpecDiff-2: Scaling Diffusion Drafter Alignment For Faster Speculative Decoding](https://mlsanity.com/paper/2511.00606/) (2025)
- [Speculative Decoding and Beyond: An In-Depth Survey of Techniques](https://mlsanity.com/paper/2502.19732/) (2025)
- [TALON: Confidence-Aware Speculative Decoding with Adaptive Token Trees](https://mlsanity.com/paper/2601.07353/) (2026)
- [Faster Language Models with Better Multi-Token Prediction Using Tensor Decomposition](https://mlsanity.com/paper/2410.17765/) (2024)
- [Token-Driven GammaTune: Adaptive Calibration for Enhanced Speculative Decoding](https://mlsanity.com/paper/2504.00030/) (2025)
- [Cost-Aware Diffusion Draft Trees for Speculative Decoding](https://mlsanity.com/paper/2606.01813/) (2026)
- [D-cut: Adaptive Verification Depth Pruning for Batched Speculative Decoding](https://mlsanity.com/paper/2607.14647/) (2026)
- [HAMburger: Accelerating LLM Inference via Token Smashing](https://mlsanity.com/paper/2505.20438/) (2025)
- [CAS-Spec: Cascade Adaptive Self-Speculative Decoding for On-the-Fly Lossless Inference Acceleration of LLMs](https://mlsanity.com/paper/2510.26843/) (2025)
- [AngelSpec: Towards Real-World High Performance Inference with Speculative Decoding](https://mlsanity.com/paper/2607.25852/) (2026)
- [Speculative Verification: Exploiting Information Gain to Refine Speculative Decoding](https://mlsanity.com/paper/2509.24328/) (2025)
- [SpecBlock: Block-Iterative Speculative Decoding with Dynamic Tree Drafting](https://mlsanity.com/paper/2605.07243/) (2026)
- [Trees from Marginals: Autoregressive drafting with factorized priors](https://mlsanity.com/paper/2607.06763/) (2026)
- [DSDE: Dynamic Speculative Decoding with KLD Stability for Real-World Serving](https://mlsanity.com/paper/2509.01083/) (2025)
- [CURE: Local Uncertainty Repair for Block-Parallel Speculative Decoding](https://mlsanity.com/paper/2608.00531/) (2026)
- [Margins, Not Windows: Training-Free Per-Step Lossy Speculative Decoding](https://mlsanity.com/paper/2609.02897/) (2026)
- [Speculative Sampling with Reinforcement Learning](https://mlsanity.com/paper/2601.12212/) (2026)
- [Dynamic Delayed Tree Expansion For Improved Multi-Path Speculative Decoding](https://mlsanity.com/paper/2602.16994/) (2026)
- [CATS: Cascaded Adaptive Tree Speculation for Memory-Limited LLM Inference Acceleration](https://mlsanity.com/paper/2605.11186/) (2026)
- [Adapting Tree-Structured Speculative Decoding to DeepSeek-V4 for Efficient Inference](https://mlsanity.com/paper/2609.24698/) (2026)
- [Tsubame: Tree Replay for Diffusion-Based Speculative Decoding](https://mlsanity.com/paper/2609.33652/) (2026)
- [SP2ec: Adaptive Self-Speculative Decoding for Vision-Language Models](https://mlsanity.com/paper/2610.18735/) (2026)

## Abstract (arXiv)

While speculative decoding has recently appeared as a promising direction for accelerating the inference of large language models (LLMs), the speedup and scalability are strongly bounded by the token acceptance rate. Prevalent methods usually organize predicted tokens as independent chains or fixed token trees, which fails to generalize to diverse query distributions. In this paper, we propose DySpec, a faster speculative decoding algorithm with a novel dynamic token tree structure. We begin by bridging the draft distribution and acceptance rate from intuitive and empirical clues, and successfully show that the two variables are strongly correlated. Based on this, we employ a greedy strategy to dynamically expand the token tree at run time. Theoretically, we show that our method can achieve optimal results under mild assumptions. Empirically, DySpec yields a higher acceptance rate and speedup than fixed trees. DySpec can drastically improve the throughput and reduce the latency of token generation across various data distribution and model sizes, which significantly outperforms strong competitors, including Specinfer and Sequoia. Under low temperature setting, DySpec can improve the throughput up to 9.1× and reduce the latency up to 9.4× on Llama2-70B. Under high temperature setting, DySpec can also improve the throughput up to 6.21×, despite the increasing difficulty of speculating more than one token per step for draft model.
