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Mamba-3

together.ai

31–40 of 59 posts

Re: Mamba-3

#31
post #29
post #7

Earlier quoted context omitted.

Mamba-3 is an architecture while diffusion is, I believe, a type of objective. So these are not mutually exclusive and therefore not comparable.

I mean I guess but the diffusion objective and the ability to do simultaneous decode both dictate pretty different architectures in practice.

Apparently not. See https://arxiv.org/abs/2511.15927v3

Re: Mamba-3

#32
post #13
post #4

I'm looking forward to comparing this to Inception 2 (the text diffusion model) which in my experience is very fast and reasonably high quality.

That's completely different. That's like saying you want to compare the Nvidia 5090 GPU to the latest Call of Duty.

You are right, people who downvoted you are just ignorant.

Re: Mamba-3

#33
post #7

Earlier quoted context omitted.

Mamba-3 is an architecture while diffusion is, I believe, a type of objective. So these are not mutually exclusive and therefore not comparable.

Not wrong, but I think it's more accurate to say: Mamba is an architecture for the middle layers of the network (the trunk) which assumes decoding takes place through an autoregressive sequence (popping out tokens in order). This is the SSM they talk about. Diffusion is an alternative to the autoregressive approach where decoding takes place through iterative refinement on a batch of tokens (instead of one at a time…

Linear architectures are at least heavily used in image diffusion models. More so in fact than in language models.

Re: Mamba-3

#34
post #14

Earlier quoted context omitted.

They don't say anything about dropping training speed.

> a departure from Mamba-2, which optimized for training speed. ?

Yes? Mamba-2 optimized for training speed compared to Mamba-1. Mamba-3 adds optimization for inference. These are pretty much version numbers.

Re: Mamba-3

#35
post #28

Is there a reason we don’t switch halfway through? ie start with a classic LLM and switch to something linear like mamba as context grows

Probably best achieved by model routing, either an indirection behind the chat UI or an API user does it themselves by calling a different API for long context queries.

Re: Mamba-3

#36

> Mamba-3 is a new state space model (SSM) designed with inference efficiency as the primary goal — a departure from Mamba-2, which optimized for training speed. The key upgrades are a more expressive recurrence formula, complex-valued state tracking, and a MIMO (multi-input, multi-output) variant that boosts accuracy without slowing down decoding. Why can’t they simply say - Mamba-3 focuses on being faster and more…

I don’t know why you’re being downvoted. As a longtime editor your version is immensely better. Looks like the original was probably not human-written.

Why would the simpler version be better for a technical audience?

Re: Mamba-3

#37
post #28

Is there a reason we don’t switch halfway through? ie start with a classic LLM and switch to something linear like mamba as context grows

Linear time complexity models are bad at in-context retrieval, which limits their performance on various tasks, so a pure linear model isn't currently feasible anyway, at least for language models. Instead they recommend mixing linear and attention layers. Presumably this mostly solves the performance problem (at least n benchmarks), but it also means the mixed architecture is no longer linear. It will still be faster and less RAM hungry in long context than a pure transformer though.

Re: Mamba-3

#39
post #28

Is there a reason we don’t switch halfway through? ie start with a classic LLM and switch to something linear like mamba as context grows

Because something linear like Mamba doesn't perform as well; so you'd have a performance cliff, where suddenly the model would get more dumb and forget a lot of what was going on.

Instead, you can get benefits from both by doing both in parallel. This can let you reduce the size of the O(n^2) attention mechanism, so while it's still quadratic, it reduces the constant quite a bit while still retaining a lot of performance, as the linear context mechanism can work for the tasks its well suited for while allowing attention to play to its strengths.

The recent Nemotron 3 Nano and Super models from NVIDIA are hybrid architectures this way, with most of their context layers as Mamba while retaining enough attention to continue to be competitive on the more complex tasks that require the quadratic attention.

See https://magazine.sebastianraschka.com/i/168650848/18-nemotro... for some discussion on this architecture

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