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DiffusionGemma Technical Report

arxiv.org

21–30 of 44 posts

Re: DiffusionGemma Technical Report

#21

I'm very interested in Diffusion text models. The concept of taking noise and adding words starting randomly all over the response, and filling in the noise from there on breaks my brain. I'm sure I have a fundamental misunderstanding of the technology, though.

Denoising is probably the weakest part of this model. There is recent research from Kaiming He showing that predicting the noise is actually not the best strategy for image generation since noise space is so large. Simply predicting the surface of the data you are trying to generate is far more representationally efficient, and perhaps in the next few months we'll see a version of that for LLMs

Diffusion language models work with a discrete output space, unlike image models that repeatedly refine a continuous output, so they don't do the noise-prediction thing anyway.

Re: DiffusionGemma Technical Report

#22

I re-implemented this one for macOS over the last couple of months: https://github.com/mmastrac/diffgemma I like the model a lot and it's fairly good at reasoning. You can also really bend it to your needs. It's designed for machines with more compute than memory bandwidth but IMO does really well on metal. I've got it up to ~15tok/s on M3-class machines, but I wager there's a bunch of perf on M5 that I just don't ha…

I have M5, but diffusion is a bad fit for metal: https://eamag.me/2026/why-parallel-diffusion-llms-are-slow-o...

Re: DiffusionGemma Technical Report

#23

I re-implemented this one for macOS over the last couple of months: https://github.com/mmastrac/diffgemma I like the model a lot and it's fairly good at reasoning. You can also really bend it to your needs. It's designed for machines with more compute than memory bandwidth but IMO does really well on metal. I've got it up to ~15tok/s on M3-class machines, but I wager there's a bunch of perf on M5 that I just don't ha…

I've also re-implemented DiffusionGemma from scratch! But with Rust+CUDA rather than macOS, I'm sure our club is a fairly small one :) About the drafting/MTP, how would that work? As I understand, MTP/drafting is mostly useful for autoregressive models, not for a diffusion model, because each canvas (in the case of DiffusionGemma at least) is fast enough, what you care about is the "convergence" time before it figure…

You can save steps when diffusing from a pre-drafted canvas instead of seeding with random noise! If you have a drafter that is good enough, steps drop by ~50% or more, and tok/s can definitely increase.

I'd be curious to see your CUDA approach - happy to combine efforts as well.

Re: DiffusionGemma Technical Report

#24
post #22

I re-implemented this one for macOS over the last couple of months: https://github.com/mmastrac/diffgemma I like the model a lot and it's fairly good at reasoning. You can also really bend it to your needs. It's designed for machines with more compute than memory bandwidth but IMO does really well on metal. I've got it up to ~15tok/s on M3-class machines, but I wager there's a bunch of perf on M5 that I just don't ha…

I have M5, but diffusion is a bad fit for metal: https://eamag.me/2026/why-parallel-diffusion-llms-are-slow-o...

That's mostly correct, but I believe the INT8 support on M5 changes the equation pretty drastically. I also believe that diffusion models generally output _better_ results if they have shaping for code (they often will miss delimiter matching inside of a canvas).

Re: DiffusionGemma Technical Report

#25

I'm very interested in Diffusion text models. The concept of taking noise and adding words starting randomly all over the response, and filling in the noise from there on breaks my brain. I'm sure I have a fundamental misunderstanding of the technology, though.

How does that break your brain? It's how basically every human writes and iterates on text..?

Does a human brain start with pure noise and then move that noise subtly towards the target?

Re: DiffusionGemma Technical Report

#26
post #21

Earlier quoted context omitted.

Denoising is probably the weakest part of this model. There is recent research from Kaiming He showing that predicting the noise is actually not the best strategy for image generation since noise space is so large. Simply predicting the surface of the data you are trying to generate is far more representationally efficient, and perhaps in the next few months we'll see a version of that for LLMs

Diffusion language models work with a discrete output space, unlike image models that repeatedly refine a continuous output, so they don't do the noise-prediction thing anyway.

Ok, you are correct. These models don't train noise predictors at all unlike first gen image diffusion

Re: DiffusionGemma Technical Report

#28

Anybody was able to run this model in a server?

Yes, it runs in vllm happily. It gets >900TPS output reliably on a single 5090 with the nvfp4 model.

It's clearly worse than vanilla 26B-A4B, and lacks some things like structured outputs, and gets some tool calls wrong.

So you have to find a usecase or a hand rolled harness that leverages the cerebras-level TPS while not going off track during (even short) tasks.

Re: DiffusionGemma Technical Report

#30

Earlier quoted context omitted.

How does that break your brain? It's how basically every human writes and iterates on text..?

Does a human brain start with pure noise and then move that noise subtly towards the target?

From what I've noticed at least for myself, there are like at least two distinct parts that don't always cooperate. There's a draft part that's random thoughts that just appear and can be converted immediately to speech, but when writing it's actually another part that takes dictation from that one, albeit silently.

If I'm just typing blind I'll somehow end up writing random homophones down with completely correct spelling, like hear instead of here, it's bizarre. So that part is sort of structured autogenerated noise that is then consciously either appended or inserted into random spots in text. Maybe it's more of an LLM first pass then diffusion refinement.

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