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DFlash

Speculative decoder in AI tools

Speeds up local LLM text generation, reported at 2-3x on some models, but critics say gains can vanish with higher memory use and drops in speed.

Speeds up local LLM text generation, reported at 2-3x on some models, but critics say gains can vanish with higher memory use and drops in speed.

20 people gave an opinion

recommend it
12
criticize it
8
approval share
60%
Each figure is one person. RecommendsCriticizes

Recommended in 6 of 13 months

  1. November 2025: not recommended
  2. December 2025: not recommended
  3. January 2026: not recommended
  4. February 2026: not recommended
  5. March 2026: not recommended
  6. April 2026: recommended
  7. May 2026: recommended
  8. June 2026: recommended
  9. July 2026: recommended
  10. August 2026: recommended
  11. September 2026: recommended
  12. October 2026: not recommended
  13. November 2026: not recommended (month in progress)

Why it doesn’t carry the badge

  • 12 people recommend itNeeds 10 or more, met.
  • 1.5 recommenders for every criticNeeds 2 to 1 or better, not met.
  • Recommended in 6 of 13 monthsNeeds 4 or more, met.

The same three rules apply to every product, and the badge can’t be bought. How the badge works

What people say about it

The reasons people give, with the number of comments that give each one. Open a reason to read what they said.

Why people recommend it

Each mark is one comment

  • Boosts token generation speed

    “There are several Mac implementations of it that show > 2x faster Qwen3.5 already.”

    Comment from 14 Apr 2026 in “Introspective Diffusion Language Models”

    “Z Lab had been publishing dflash addons and boosting their tgen 2-3x”

    Comment from 10 Jul 2026 in “Don't discontinue Gemini 2.5 Flash”

    “DFlash is currently a SOTA speculative decoding method”

    Comment from 10 Jun 2026 in “DiffusionGemma: 4x Faster Text Generation”
  • Enables models with no other path

    “Before this repo, there was no path to run this... SGLang's GGUF path for this model is broken.”

    Comment from 20 Apr 2026 in “We got 207 tok/s with Qwen3.5-27B on an RTX 3090”

    “Before this repo, there was no path to run this”

    Comment from 20 Apr 2026 in “We got 207 tok/s with Qwen3.5-27B on an RTX 3090”

What people warn about

Each mark is one comment

  • Speed can drop off sharply

    “model performance suddenly drops off a cliff like maybe there is some memory management issue”

    Comment from 10 Aug 2026 in “Meta Muse Glimmer – open weights 30B local coding model”

    “performance suddenly drops off a cliff if I have DFlash enabled”

    Comment from 10 Aug 2026 in “Meta Muse Glimmer – open weights 30B local coding model”

    “it craters to ~9 t/s with it on, miss rate exceeding 50%”

    Comment from 10 Aug 2026 in “Meta Muse Glimmer – open weights 30B local coding model”
  • Higher memory use and OOM crashes

    “tgen is way up, but keep the number low, acceptance rate is terrible beyond half a dozen and it requires more memory”

    Comment from 9 Jul 2026 in “Hy3”

    “Have had issues with the dflash drafter and vllm, crashes, OOMs, broken thinking”

    Comment from 22 Jul 2026 in “Running Laguna S 2.1 locally on Apple Silicon: 52 tok/s with 38.5 GB peak memory”
  • Slow or no gain for some

    “Spec decode (DFlash, n-gram) didn't give a good boost”

    Comment from 11 Sep 2026 in “So you want to use OpenRouter?”

    “Dflash2 is really slow for me, like sub 10 TG”

    Comment from 18 Sep 2026 in “Shapelearn Qwen 3.8 27B (13.1 GB VRAM)”
  • Broken output or failed tool calls

    “Have had issues with the dflash drafter and vllm, crashes, OOMs, broken thinking”

    Comment from 22 Jul 2026 in “Running Laguna S 2.1 locally on Apple Silicon: 52 tok/s with 38.5 GB peak memory”

    “DFlash2's tool call fails on python syntax.”

    Comment from 19 Aug 2026 in “DFlash 2: Keep Drafting Parallel”

What people recommend instead

The same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.

DFlash compared with 1 alternative
ProductRecommendCriticizeApprovalMonthsOwnedBadge
DFlashThis page12860%6——
Orthrus-Qwen350100%1——

What people said

21 of the 22 comments that mention it, newest first. Each links to the original comment.

“help to do one forwards pass and get 6-7 tokens out of it”

RecommendsComment from 23 Sep 2026 in “Tokens too cheap to meter”

“Dflash2 is really slow for me, like sub 10 TG”

CriticizesComment from 18 Sep 2026 in “Shapelearn Qwen 3.8 27B (13.1 GB VRAM)”

“Spec decode (DFlash, n-gram) didn't give a good boost”

CriticizesComment from 11 Sep 2026 in “So you want to use OpenRouter?”

“setup llama.cpp with dflash2 for you”

RecommendsComment from 8 Sep 2026 in “Speculative Decoding in vLLM on AMD GPUs”

“Dflash (2) will push your TG even further”

RecommendsComment from 25 Aug 2026 in “Qwen 3.8-Flash-Next releasing tomorrow (125B a6B)”

“DFlash2's tool call fails on python syntax.”

CriticizesComment from 19 Aug 2026 in “DFlash 2: Keep Drafting Parallel”

“has made low memory bandwidth model usage so much nicer”

RecommendsComment from 19 Aug 2026 in “DFlash 2: Keep Drafting Parallel”

“I have exactly the same issue on a M1 Max as well.”

CriticizesComment from 10 Aug 2026 in “Meta Muse Glimmer – open weights 30B local coding model”

“it craters to ~9 t/s with it on, miss rate exceeding 50%”

CriticizesComment from 10 Aug 2026 in “Meta Muse Glimmer – open weights 30B local coding model”

“model performance suddenly drops off a cliff like maybe there is some memory management issue”

CriticizesComment from 10 Aug 2026 in “Meta Muse Glimmer – open weights 30B local coding model”

“performance suddenly drops off a cliff if I have DFlash enabled”

CriticizesComment from 10 Aug 2026 in “Meta Muse Glimmer – open weights 30B local coding model”

“Have had issues with the dflash drafter and vllm, crashes, OOMs, broken thinking”

CriticizesComment from 22 Jul 2026 in “Running Laguna S 2.1 locally on Apple Silicon: 52 tok/s with 38.5 GB peak memory”

“Z Lab had been publishing dflash addons and boosting their tgen 2-3x”

RecommendsComment from 10 Jul 2026 in “Don't discontinue Gemini 2.5 Flash”

“This is actually what I was hoping would happen when the deepspec stuff dropped!”

RecommendsComment from 9 Jul 2026 in “Hy3”

“tgen is way up, but keep the number low, acceptance rate is terrible beyond half a dozen and it requires more memory”

MixedComment from 9 Jul 2026 in “Hy3”

“DFlash is currently a SOTA speculative decoding method”

RecommendsComment from 10 Jun 2026 in “DiffusionGemma: 4x Faster Text Generation”

“you should be using dflash with that model, look it up”

RecommendsComment from 20 May 2026 in “Qwen3.7-Max: The Agent Frontier”

“Before this repo, there was no path to run this”

RecommendsComment from 20 Apr 2026 in “We got 207 tok/s with Qwen3.5-27B on an RTX 3090”

“Q4 is a non-starter for real work. The fact that you're still trying to defend it tells me you haven't used this for anything other than token/sec racing.”

CriticizesComment from 20 Apr 2026 in “We got 207 tok/s with Qwen3.5-27B on an RTX 3090”

“Before this repo, there was no path to run this... SGLang's GGUF path for this model is broken.”

RecommendsComment from 20 Apr 2026 in “We got 207 tok/s with Qwen3.5-27B on an RTX 3090”

“There are several Mac implementations of it that show > 2x faster Qwen3.5 already.”

RecommendsComment from 14 Apr 2026 in “Introspective Diffusion Language Models”

Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.