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Exponentially faster language modelling

arxiv.org

41–50 of 150 posts

Re: Exponentially faster language modelling

#41
post #4

Abstract: > Language models only really need to use an exponential fraction of their neurons for individual inferences. As proof, we present UltraFastBERT, a BERT variant that uses 0.3% of its neurons during inference while performing on par with similar BERT models. UltraFastBERT selectively engages just 12 out of 4095 neurons for each layer inference. This is achieved by replacing feedforward networks with fast fee…

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Re: Exponentially faster language modelling

#43

Link to previous paper: https://arxiv.org/abs/2308.14711 An attempt at a summary: They use a sigmoid function to make differentiable "soft" branches, and stack them to construct a binary tree, with the goal of only taking one branch at inference time (but training the whole tree) leading to log(W) instead of W inference cost. They gradually harden the branches so they become hard branches at the end of training. A br…

From the previous paper you cited >Pushing FFFs to the limit, we show that they can use as little as 1% of layer neurons for inference in vision transformers while preserving 94.2% of predictive performance.

This feels like that often misinterpreted Einstein meme/qoute about humans only using a fraction of their brain power.

Is this only for inference though? could it boost training?

Re: Exponentially faster language modelling

#45

Earlier quoted context omitted.

They sure as hell have no incentives to make Neural Network faster and more accessible, for starters.. (Considering they right now make more money and have more control, the less accessible and the more computation-hungry AI models are) To be fair, this approach (claims to) only speed up inference, not training, so all the GPUs are needed anyway.

They certainly have an incentive to keep these kinds of improvements in-house and not publish them, since they are commercial entities and this represents a competitive advantage.

I think Nvidia might have an incentive for this not to exist.

edit: but you are right for the AI companies not open sourcing their models it's an advantage to have it when others don't

Re: Exponentially faster language modelling

#46

hugging face model https://huggingface.co/pbelcak/UltraFastBERT-1x11-long

> This model is provided only as sanity check for research purposes, it is untested and unfit for deployment. I guess this means it isn't pretrained yet? Is it still just random weights?

"Unfit for deployment" or "not intended for deployment" is semi-standard wording for research models that are just raw language models with none of the safety/bias/offensiveness filtering that is usually desired for product applications. For example, if you deploy it as a customer-service chatbot, it might tell your customers to kill themselves, or call them racial slurs.

It doesn't mean that there's anything technically wrong with the language model per se as a model of language, just that there has been no effort made to ensure it's fit to be deployed as-is for any given generative-AI use case, and the model authors would prefer you didn't do that.

Re: Exponentially faster language modelling

#47

Link to previous paper: https://arxiv.org/abs/2308.14711 An attempt at a summary: They use a sigmoid function to make differentiable "soft" branches, and stack them to construct a binary tree, with the goal of only taking one branch at inference time (but training the whole tree) leading to log(W) instead of W inference cost. They gradually harden the branches so they become hard branches at the end of training. A br…

[deleted]

Re: Exponentially faster language modelling

#48

Link to previous paper: https://arxiv.org/abs/2308.14711 An attempt at a summary: They use a sigmoid function to make differentiable "soft" branches, and stack them to construct a binary tree, with the goal of only taking one branch at inference time (but training the whole tree) leading to log(W) instead of W inference cost. They gradually harden the branches so they become hard branches at the end of training. A br…

From the previous paper you cited >Pushing FFFs to the limit, we show that they can use as little as 1% of layer neurons for inference in vision transformers while preserving 94.2% of predictive performance. This feels like that often misinterpreted Einstein meme/qoute about humans only using a fraction of their brain power. Is this only for inference though? could it boost training?

That's an interesting question. It actually provides a nice way to parallelized training: Pretrain e.g. the first 3 branch levels, which effectively fragments the model into 8 separate parts, which you can continue training across 8 independent servers/nodes with no further communication between the nodes. A central server would run the 1st 3 levels and mark parts of the training set that each node has to train on. Maybe you could do this for the whole network and distribute the training in SETI@HOME style all over the world.

Hold on, you don't even need to freeze the branches completely: each node could train 1 branch on the path to its leaf node and communicate a change in the branch node to a central server, so you can distribute training without having to pre-freeze the branches. Still would need some pre-training though, and the splits would change slowly, and the attention mechanism could complicate things.

Currently distributed neural network training SETI@HOME style looks like a complete pipe dream that nobody is taking seriously. But a smart branching mechanism like this could suddenly make it possible. Folding@home reached 1.5 exaflops, which made it the world's largest supercomputer. Imagine the models we could train that way, they would far surpass whatever OpenAI or Google could train and would be public.

Re: Exponentially faster language modelling

#49

Earlier quoted context omitted.

They certainly have an incentive to keep these kinds of improvements in-house and not publish them, since they are commercial entities and this represents a competitive advantage.

I think Nvidia might have an incentive for this not to exist. edit: but you are right for the AI companies not open sourcing their models it's an advantage to have it when others don't

I'm actually not sure about Nvidia, due to https://en.wikipedia.org/wiki/Jevons_paradox

Re: Exponentially faster language modelling

#50

Earlier quoted context omitted.

>Flops really are quite cheap by now, e.g. vision inference chip ~$2/teraflop/s !! I'm really interested, can you share where you got these numbers?

Axelera [1] or Halio [2] give you 100-200tflop for ~$200. 8-bit ops, inference only, low memory embedded, excluding the host, implied utilization from FPS specs is ~20% But the trend is there. There are also newer ADAS/AV units from China which claim 1000tflops and cant really cost more than $1000/$2000 per car. These are all tiled designed (see also dojo/tesla) heavily over-weighed on flops vs memory [1] https://www…

You can't get flops on a Hailo-8, they're fixed-point only. As much as these specialised inference chips are cool, we're a long way from just being able to drop them in where a GPU was. Not to mention the memory is hugely constrained. The Hailo chips I've worked with were all limited to 20MiB for the weights which is a squeeze even at 4-bit.
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