---
title: "Exploring Speculative Decoding in vLLM on AMD GPUs"
url: https://daily.dev/posts/exploring-speculative-decoding-in-vllm-on-amd-gpus-3xgpvjp6n
source_url: https://vllm.ai/blog/2026-08-23-speculative-decoding-amd-gpus
type: article
source: "vLLM"
published: 2026-08-23T02:05:56.348Z
updated: 2026-08-23T02:06:27.229Z
tags: ["amd", "ai-inference", "vllm"]
reading_time: 67
upvotes: 1
comments: 0
language: en
---

> ## Documentation Index
> Fetch the complete documentation index at: https://daily.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Exploring Speculative Decoding in vLLM on AMD GPUs

**[vLLM](https://daily.dev/sources/vllm)** · 67 min read · 1 upvotes · 0 comments

## Summary

A detailed technical walkthrough of speculative decoding in vLLM running on AMD Instinct MI300X and MI355X GPUs with ROCm. It covers five drafting approaches (native MTP, Gemma 4 MTP, EAGLE-3, DFlash, and DSpark), explains how each draft component uses target-model information and generates candidate tokens, and shows how to configure them via --speculative-config. Extensive benchmarks across Gemma, Qwen, MiniMax, and Kimi models show throughput gains ranging from below baseline to over 2.8x depending on model, workload, and proposal length (num_speculative_tokens). Practical tuning guidance covers sweeping proposal lengths, monitoring acceptance rate and mean accepted length, and matching sweep depth to workload type. A section also outlines how to train a new speculator using the vLLM Speculators toolkit.

## Full article

daily.dev links to this article rather than hosting it. Read it at the original source: <https://vllm.ai/blog/2026-08-23-speculative-decoding-amd-gpus>

## Questions this post answers

### What speculative decoding methods does vLLM support for AMD GPUs?

vLLM's --speculative-config supports four method values: mtp, eagle3, dflash, and dspark, covering native MTP, Gemma 4 MTP, EAGLE-3, DFlash, and DSpark drafting approaches. Native MTP requires no separate draft checkpoint, while the others need a matching speculator model specified via the model field, plus a chosen num_speculative_tokens value.

_Engineers tuning inference throughput can follow ongoing vLLM tooling coverage on daily.dev._

### How does DFlash differ from EAGLE-3 in speculative decoding?

DFlash predicts an entire block of future token positions in parallel in a single forward pass, while EAGLE-3 generates draft tokens autoregressively, with each token depending on the previous one. Both fuse hidden states from multiple target-model layers, but DFlash injects this context as Key/Value pairs available in every draft layer, whereas EAGLE-3 combines it only at the input with the sampled-token embedding.

_Teams choosing between parallel and sequential drafting strategies can track comparisons like this on daily.dev._

### What throughput speedups did DFlash and Gemma 4 MTP achieve on gemma-4-26B-A4B-it?

On gemma-4-26B-A4B-it, DFlash reached up to 2.87x throughput on MATH500 and 2.79x on HumanEval, while Gemma 4 MTP reached 2.74x on GSM8K and 2.62x on MBPP. EAGLE-3 measurements on the same model ranged from 2.11x to 2.27x across the four datasets, with proposal length (N) tuned per workload during testing on AMD MI300X/MI355X GPUs.

_Practitioners benchmarking inference speedups can follow real-world throughput numbers on daily.dev._

## Similar posts on daily.dev

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- [EAGLE-3 Speculative Decoding on AMD Instinct GPUs: Training and Serving with vLLM and AMD Quark](https://daily.dev/posts/eagle-3-speculative-decoding-on-amd-instinct-gpus-training-and-serving-with-vllm-and-amd-quark-x5yf4izas) · vLLM · 0 upvotes · 0 comments
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---

Tags: [#amd](https://daily.dev/tags/amd), [#ai-inference](https://daily.dev/tags/ai-inference), [#vllm](https://daily.dev/tags/vllm)

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