TAPS: Task Aware Proposal Distributions for Speculative Sampling
- URL: http://arxiv.org/abs/2603.27027v1
- Date: Fri, 27 Mar 2026 22:34:20 GMT
- Title: TAPS: Task Aware Proposal Distributions for Speculative Sampling
- Abstract summary: We study how much speculative decoding quality depends on the draft training distribution.<n>We show that MathInstruct-trained drafts are strongest on reasoning benchmarks, while ShareGPT-trained drafts are strongest on MT-Bench.<n>We also study how to combine specialized drafters at inference time.
- Score: 43.87155816175029
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Speculative decoding accelerates autoregressive generation by letting a lightweight draft model propose future tokens that a larger target model then verifies in parallel. In practice, however, draft models are usually trained on broad generic corpora, which leaves it unclear how much speculative decoding quality depends on the draft training distribution. We study this question with lightweight HASS and EAGLE-2 drafters trained on MathInstruct, ShareGPT, and mixed-data variants, evaluated on MT-Bench, GSM8K, MATH-500, and SVAMP. Measured by acceptance length, task-specific training yields clear specialization: MathInstruct-trained drafts are strongest on reasoning benchmarks, while ShareGPT-trained drafts are strongest on MT-Bench. Mixed-data training improves robustness, but larger mixtures do not dominate across decoding temperatures. We also study how to combine specialized drafters at inference time. Naive checkpoint averaging performs poorly, whereas confidence-based routing improves over single-domain drafts and merged-tree verification yields the highest acceptance length overall for both backbones. Finally, confidence is a more useful routing signal than entropy: rejected tokens tend to have higher entropy, but confidence produces much clearer benchmark-level routing decisions. These results show that speculative decoding quality depends not only on draft architecture, but also on the match between draft training data and downstream workload, and that specialized drafters are better combined at inference time than in weight space.
Related papers
- DBLAST: Dependent Block Drafting for Stochastic Speculative Decoding [26.72775347772003]
We show that the accepted draft length degrades as the entropy of the target sampling distribution increases.<n>We propose a dependent block drafter based on a low-rank latent mixture over token positions, complemented by an acceptance-oriented training objective.
arXiv Detail & Related papers (2026-08-05T22:49:54Z) - Before Thinking, Learn to Decide: Proactive Routing for Efficient Visual Reasoning [87.18590662029432]
We propose PRP, a Proactive Routing Paradigm that enables early decision-making by jointly evaluating the competence of both the draft and target models.<n>Our draft Rating Learning (DRL) equips the draft model with an internal confidence estimator, while Joint Rating Learning (JRL) predicts how well the target model can handle a given query.<n>These ratings enable fine-grained, instance-level textbfProactive Routing and substantially accelerate inference without compromising overall performance.
arXiv Detail & Related papers (2026-06-29T12:30:24Z) - PriFT: Prior-Support Guided Supervised Fine-Tuning [74.65198014829393]
Supervised fine-tuning (SFT) is an efficient approach for downstream task adaptation.<n>SFT fits fixed demonstrations token by token, including targets poorly aligned with the model's pretrained distribution.<n>We propose PriFT, which derives token weights from a frozen pretrained reference to obtain a stable reweighting signal unaffected by fine-tuning.
arXiv Detail & Related papers (2026-06-08T12:14:06Z) - Draft-OPD: On-Policy Distillation for Speculative Draft Models [49.23782868133977]
Speculative decoding accelerates large language model inference by pairing a target model with a lightweight draft model whose proposed tokens are verified in parallel.<n>We propose Draft-OPD, which uses target-assisted rollout for stable continuations and replays drafting from the verification-exposed error positions.
arXiv Detail & Related papers (2026-05-28T04:30:22Z) - DiffuSpec: Unlocking Diffusion Language Models for Speculative Decoding [66.40658898418316]
We present DiffuSpec, a training-free drop-in framework that uses a pretrained diffusion language model (DLM) to produce multi-token drafts in a single forward pass.<n>Across benchmarks, DiffuSpec yields up to 3x wall-clock speedup, establishing diffusion-based drafting as a robust alternative to autoregressive drafters for speculative decoding.
arXiv Detail & Related papers (2025-09-28T07:00:15Z) - POSS: Position Specialist Generates Better Draft for Speculative Decoding [29.847485296491204]
Speculative decoding accelerates Large Language Model (LLM) inference.<n>Recent studies leverage the hidden state of the target model to enhance draft model prediction accuracy.<n>We propose Position Specialists (PosS), which consist of multiple position-specialized draft layers to generate tokens at assigned position(s)
arXiv Detail & Related papers (2025-06-04T04:30:30Z) - GRIFFIN: Effective Token Alignment for Faster Speculative Decoding [33.26750782762635]
GRIFFIN is a novel framework that incorporates a token-alignable training strategy and a token-alignable draft model.<n>Experiments on LLaMA, Vicuna, Qwen and Mixtral models demonstrate that GRIFFIN achieves an average acceptance length improvement of over 8% and a speedup ratio exceeding 7%.
arXiv Detail & Related papers (2025-02-16T07:06:00Z) - Jakiro: Boosting Speculative Decoding with Decoupled Multi-Head via MoE [15.003006630308517]
Speculative decoding (SD) accelerates large language model inference by using a smaller draft model to predict multiple tokens.<n>We propose Jakiro, leveraging Mixture of Experts (MoE), where independent experts generate diverse predictions.<n>Our method significantly boosts prediction accuracy and achieves higher inference speedups.
arXiv Detail & Related papers (2025-02-10T09:24:06Z) - Draft Model Knows When to Stop: Self-Verification Speculative Decoding for Long-Form Generation [64.59292053188264]
Experimental results on mainstream SD benchmarks as well as reasoning-heavy benchmarks demonstrate the superior performance of SVIP.<n>SVIP is a training-free dynamic length policy for speculative decoding systems that adaptively determines the lengths of draft sequences by referring to the draft entropy.
arXiv Detail & Related papers (2024-11-27T15:53:17Z) - Speculative Decoding with CTC-based Draft Model for LLM Inference Acceleration [14.011702040133848]
We propose a CTC-based draft model which strengthens the correlations between draft tokens during the draft phase.<n>Experiment results show that compared to strong baselines, the proposed method can achieve a higher acceptance rate and hence a faster inference speed.
arXiv Detail & Related papers (2024-11-25T14:10:21Z) - AdaEDL: Early Draft Stopping for Speculative Decoding of Large Language Models via an Entropy-based Lower Bound on Token Acceptance Probability [5.421949344085942]
We show that AdaEDL consistently outperforms static draft-length speculative decoding by 10%-57%.
We also show that AdaEDL is more robust than these techniques and preserves performance in high-temperature scenarios.
arXiv Detail & Related papers (2024-10-24T01:13:43Z) - Distributionally Robust Models with Parametric Likelihood Ratios [123.05074253513935]
Three simple ideas allow us to train models with DRO using a broader class of parametric likelihood ratios.
We find that models trained with the resulting parametric adversaries are consistently more robust to subpopulation shifts when compared to other DRO approaches.
arXiv Detail & Related papers (2022-04-13T12:43:12Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.