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What happens if we remove 50 percent of Llama?

neuralmagic.com

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Re: What happens if we remove 50 percent of Llama?

#91
post #76

Earlier quoted context omitted.

>With the discovery that transformers lack reasoning capabilities The only paper I have seen claiming this studied only lightweight open-source models (<27B, mostly 2B and 8B). The also included o1 and 4o for reference, which kind of broke their hypothesis, but they just left that part out of the conclusion. Not even kidding, their graphs show o1 and 4o having strong performance in their benchmarks, but the conclusio…

https://arxiv.org/abs/2410.05229 An 18% drop in accuracy (figure 8) is not insignificant. Even 4o suffered 10% loss (figure 6), and 4o isn't a small llm. Competent performance should have near zero performance loss. The simplest benchmark merely changes things like "john had 4 apples" to "Mary had 4 oranges." Performance loss due to inconsequential tokens changing is the very definition of over-fitting.

>The simplest benchmark merely changes things like "john had 4 apples" to "Mary had 4 oranges."

Those models (4o, o1-mini, preview) don't see any drop at all on those benchmarks. The only benchmark that see drops with the SOTA models is the one they add, "seemingly relevant but ultimately irrelevant information".

Humans can and do drop in performance when presented with such alterations. Are they better than LLMs in that case ? Who knows ? Because these papers don't bother testing human baselines.

Re: What happens if we remove 50 percent of Llama?

#93

I'm curious - what happens if one prunes the halved model again (if that's possible with the same method), would it start losing accuracy?

Let’s take it a step further and accept some inaccuracy. If we apply the Pareto principle[1], we should get 80% of the accuracy for 20% of the size.

Compounding that four times, we should get .8^4 = 40% of the accuracy for .2^4 = .16% of the size.

That’d be about 1 GB for the current largest model.

[1]: https://en.wikipedia.org/wiki/Pareto_principle

Re: What happens if we remove 50 percent of Llama?

#94
post #63
post #22

After reading the article it seems to me that this is more like synaptic pruning where weak connections between neurons are eliminated in order to increase the efficiency of the neurons. Interesting to see that this also works for LLMs. https://en.wikipedia.org/wiki/Synaptic_pruning

The issue is that no one fully understands why synaptic pruning occurs in biology. Large language models have no direct connection to biological systems, and pruning in LLMs is no exception.

A number of things that work for biological systems (humans) work for LLMs too:

- after the answer, ask it "are you sure?" (from the office tv series: "is it a stupid thing to do? if it is, don't do it") - chain of thought, step-by-step thinking - different hats (godfather style: piecetime vs. wartime consigliere): looking at the problem from different points of view (at the same time or in stages). For example, first draft: stream of consciousness answer, second iteration: critic/editor/reviewer (produces comments), third (address comments), repeat for some time - collaborative work of different experts(MoE), delegate specific tasks to specialists - [deliberate] practice with immediate feedback

Re: What happens if we remove 50 percent of Llama?

#95
post #21

Earlier quoted context omitted.

The main constraint on consumer GPUs is the VRAM - you can pretty much always do inference reasonably fast on any model that you can fit. And most of that VRAM is the loaded parameters, so yes, this should help with running better models locally. I wonder how much they'd be able to trim the recent QwQ-32b. That thing is actually good enough to be realistically useful, and runs decently well with 4-bit quantization, w…

Does this mean that the model will be half the size? If a 32B model@4bit normally requires 16 GB VRAM, at half the size, it could be run @8bit with 16 GB VRAM? Isn't that tradeoff a great improvement? I assume the improved bit precision will more than compensate for the loss related to removal?

There is some improvement going from 4-bit to 8-bit quantization, but if you have VRAM to spare for that, you usually see more benefit from running a 2x larger model at 4-bit. So in scenarios where an LM already fits the existing VRAM budget, I would expect larger models instead.

The other thing is that VRAM is used not just for the weights, but also for prompt processing, and this last part grows proportionally as you increase the context size. For example, for the aforementioned QwQ-32, with base model size of ~18Gb at 4-bit quantization, the full context length is 32k, and you need ~10Gb extra VRAM on top of weights if you intend to use the entirety of that context. So in practice, while 30b models fit into 24Gb (= a single RTX 3090 or 4090) at 4-bit quantization, you're going to run out of VRAM once you get past 8k context. Thus the other possibility is that VRAM saved by tricks like sparse models can be used to push that further - for many tasks, context size is the limiting factor.

Re: What happens if we remove 50 percent of Llama?

#96

I'm curious - what happens if one prunes the halved model again (if that's possible with the same method), would it start losing accuracy?

I was thinking the same. On HF, I see 4bit gguf of this 2:4 model, and I'm like...that works?

Re: What happens if we remove 50 percent of Llama?

#97
post #60

Earlier quoted context omitted.

I didn't say low intellect but , as also a functioning autist (as most of us are) i know myself that i am something wrong compare to other people who are quite different.

I don't think you are something wrong, I think it's wonderful that brains can be so different. I'm fascinated by every type of neurodivergence. You should be proud of what you are, not ashamed of being "something wrong".

That might be true if we lived in a true meritocracy, but we don't. Struggling with interpersonal relationships and communication is a major hindrance.

Re: What happens if we remove 50 percent of Llama?

#98

All of these smaller model paradigm suggests that we need to incorporate pruning into model training. Neat was one of my favorite algorithms of all time. Same thing with BitNet models which keep showing the information you need is not that much for neural networks. And again, it is same with us, we use much less energy than a regular network so there seems to be immense waste of energy training these models. My intiu…

> This basically shows over 50% of the neural net is gibberish! The reason being is that the objective function simply does not include it.

This is a mischaracterization of sparsity. Performance did drop, so the weights are not gibberish. Training vs pruning, you can't train into the final state, you can only prune there.

Re: What happens if we remove 50 percent of Llama?

#99
post #84

Earlier quoted context omitted.

I seem to recall that there a recent theory paper that got a best paper award, but can't find it. If I remember correctly, their counter-intuitive result was that big overparameterized models could learn more efficiently, and were less likely to get trapped in poor regions of the optimization space. [This is also similar to how introducing multimodal training gives an escape hatch to get out of tricky regions.] So wi…

The lottery ticket hypothesis paper from 2018?

Seems this way. Gigantic model, hit the jackpot, prune the nonsense. It doesn't seem like smaller models are enough tickets.
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