Speculative decoding
EAGLE-2
EAGLE-2: Faster Inference of Language Models with Dynamic Draft Trees
Heavily superseded — a standard baseline that newer methods routinely beat
10 papers critique it · 21 beat it on benchmarks
What papers say
Verbatim critique sentences, each from a paper that cites EAGLE-2 as a baseline.
to achieve the benefits claimed by EAGLE-2, the target model must verify nearly twice as many tokens, which is not a fair comparison. When aligning for the size of the token tree, the benefit of EAGLE-2 in terms of accept length is only 11%. Moreover, due to the additional latency introduced by the dynamic strategy, the wall-clock time of EAGLE-2 is more.
“When directly applying speculative decoding algorithms on heterogeneous architectures, the acceleration effect is only improved by 1.57 times”
“it is not dynamic in the depth or width of the beam search. However, a dynamic depth would allow the draft model to be called a variable number of times per target model call, depending the likelihood of each sequence in the current beam being correct”
“In the speculative decoding context, EAGLE-2 adapts draft tree depth based on confidence, but does not consider compression.”
“The results of reliable experiments across various integration schemes show that EAGLE-2 provides limited benefit for 4-bit weight quantized models (W4A16 and W4A8), indicating a potential conflict.”
“EAGLE2 suffers from a token misalignment rate of 48% during training, resulting in suboptimal acceptance lengths and limiting its effectiveness”
“EAGLE-2 prunes low-confidence branches via the draft head's per-token scores, growing deeper along well-predicted paths; this adapts the shape to within-drafter quality variation but requires a trained head and lacks optimality guarantees.”
“EAGLE-2~li2024eagle used static trees with fixed-width branching, which are less effective under varying draft confidence”
“Building with EAGLE-2~li2024eagle2, HASS achieves 8\%-16\% acceptance length improvement over it”
“Many SD pipelines require training a drafting model for multiple epochs over large datasets, or intensive model distillation from full teacher distributions over data ankner2024hydra, cai2024medusa, li2024eagle, li2024eagle-2, zhang2023draft.”
Beaten on benchmarks
Head-to-head results where a newer method reports beating EAGLE-2. Values are copied from the source paper's tables — verify against the cited paper.
FastGRPO beats EAGLE-2
2.91 vs 1.12
Gen SR · [Q2.5-7B-I, SimpleRL-Abel-Level3to5]
FastGRPO: Accelerating Policy Optimization via Concurrency-aware Speculative Decoding and Online Draft LearningScylla beats EAGLE-2
2150 vs 980
Throughput · [Batch size 64]
Scaling Laws for Speculative DecodingToolSpec beats EAGLE-2
3.48 vs 2.12
Overall Speedup · [Qwen2.5-14B-Instruct]
ToolSpec: Accelerating Tool Calling via Schema-Aware and Retrieval-Augmented Speculative DecodingRASD beats EAGLE-2
2.78 vs 1.73
tau · [Q 14B, Temperature = 0]
RASD: Retrieval-Augmented Speculative DecodingHierSpec beats EAGLE-2
98.19 vs 63.44
Tok/s · [W4A16 Llama-3-70B, d=6]
Speculative Decoding Meets Quantization: Compatibility Evaluation and Hierarchical Framework DesignmyFrame beats EAGLE-2
133.10 vs 100.24
Tokens/s · [Vicuna-7B]
When, What, and How: Rethinking Retrieval-Enhanced Speculative DecodingC2T β=0.85 beats EAGLE-2
226569 vs 317668
γ (candidate tokens) · [E-2 TopN=26]
C2T: A Classifier-Based Tree Construction Method in Speculative DecodingGRIFFIN beats EAGLE-2
4.67 vs 3.80
tau · [Qwen2-7B, Temperature=0, MT-Bench]
GRIFFIN: Effective Token Alignment for Faster Speculative DecodingSpecUCB beats EAGLE-2
151.37 vs 126.01
Tokens/s · [Qwen2-7B-Instruct, Debug Bench]
BanditSpec: Adaptive Speculative Decoding via Bandit AlgorithmsPRISM beats EAGLE-2
201.51 vs 168.26
TPS · [LLaMA-3-8B, T=0]
PRISM: Parametrically Refactoring Inference for Speculative Sampling Draft ModelsDREAM-S beats EAGLE-2
3.16 vs 2.69
Average speedup ratio (S) · [LLaVA-v1.6-Vicuna-13B, Temperature=0]
DREAM-S: Speculative Decoding with Searchable Drafting and Target-Aware Refinement for Multimodal GenerationSAM-Decoding beats EAGLE-2
2.81 vs 2.41
Speedup · [HAGRID]
SAM Decoding: Speculative Decoding via Suffix Automaton
What to use instead
Recent methods in the same sub-problem, not yet superseded in the knowledge base — arXiv benchmark leaders, not vetted production recommendations.
- DREAM-SDREAM-S: Speculative Decoding with Searchable Drafting and Target-Aware Refinement for Multimodal GenerationMay 30, 2026
- May 14, 2026
- SpecForgeSpecForge: A Flexible and Efficient Open-Source Training Framework for Speculative DecodingMar 19, 2026
- Mar 13, 2026
- Feb 17, 2026
- Oct 22, 2025
- Oct 22, 2025
- Oct 17, 2025
- Draft, Verify, & Improve (DVI)Draft, Verify, and Improve: Toward Training-Aware Speculative DecodingOct 6, 2025
- FastGRPOFastGRPO: Accelerating Policy Optimization via Concurrency-aware Speculative Decoding and Online Draft LearningSep 26, 2025