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Numbers every LLM developer should know

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Re: Numbers every LLM developer should know

#71
post #32

> ~$1 million: Cost to train a 13 billion parameter model on 1.4 trillion tokens MosaicML claims they trained a 7 billion parameter on 1 trillion tokens with a budget of $200k. https://www.mosaicml.com/blog/mpt-7b Does training cost scale linearly with model size and token count? If so, that suggests a lower bound of $600k to train the 13 billion params model. (Still roughly the same magnitude)

[Author] Mosaic must be getting some kind of sweetheart deals on A100 80GB and A100 40GB. The prices they are quoting are not what say the AWS on-demand prices are. They quote $2 per GPU for A100 40GB and $2.50 for A100 80GB. That's literally half the AWS on-demand rate for A100s here: https://aws.amazon.com/ec2/instance-types/p4/ And these are impossible to get. We tried to get some for Anyscale, and we were told th…

There is no possible way for anyone buying 1M worth of compute to get list pricing.

Re: Numbers every LLM developer should know

#72
post #18

Earlier quoted context omitted.

[Author] Completely disagree. Any analysis shows that you see perplexity reduction at 4 bits. Have a look at llama.cpp's results here: https://github.com/ggerganov/llama.cpp#quantization 4 bit has a perplexity score 0.13 or so higher.

You're just wrong. You're looking at the wrong numbers. The perplexity score of a model with twice the parameters in half the bits (4bit) is FAR LOWER (ie better). If you are limited to X RAM and have two 16bit models of size 4X and 2X then the 4X model in 4bit will always be far superior to the 2X model in 8bit, with far lower perplexity. Compare 13B's 4bit perplexity of 5.3607 to 7B's 8bit perplexity of 5.9069. Tha…

A stupid question but...what about a 16x model in 1bit?

Re: Numbers every LLM developer should know

#74
post #64

Earlier quoted context omitted.

Human reading speed varies by a factor of 10 or more between individuals, while speaking speed is much more consistent.

Even my own reading speed even varies by a factor of 5 day to day, depending on how much reading I've been doing, sleep I've gotten, etc.

Plus, whether I am reading light fiction versus technical documentation.

Re: Numbers every LLM developer should know

#75
post #19

> Of course there are efforts to reduce this, notably llama.cpp which runs a 13 billion parameter model on a 6GB GPU by quantizing aggressively down to 4 bits (and 8 bits without too much impact), but that’s atypical. No, 4bit quantization is the typical case. At 4bit you can fit twice the parameters of 8bit in the same space for far better performance/perplexity/quality. Running LLMs higher than 4bit is atypical and…

Can somebody please explain how quantization below 8 bit works? Since a byte is the smallest addressable unit I think, is the dimensionality of the weights somehow reduced?

Generally, since the memory is byte addressable, you load data which is packed into bytes. It is the compute instructions that use the specified bits needed.

So in this case one would load a byte which would have 2 4b data, and then you would have a 4b ADD or MAC which would operate on them.

If you don't have them then you need to sign/zero extend or convert the smaller bit-widths to 8/16/32b whichever is available.

Re: Numbers every LLM developer should know

#77

Earlier quoted context omitted.

But I'd say LLMs produce content faster than I can read or write it, because they can produce content which is really dense. Ask GPT-4 a question and then answer it yourself. Maybe your answer will be as good or better than GPT-4's but GPT-4 writes its answer a lot faster.

It certainly doesn't produce content as fast as I can read it.

Only if you use gpt-4. gpt-3.5-turbo is much faster, and gpt-4 is only going to get faster as GPUs get faster.

Re: Numbers every LLM developer should know

#78
post #72

Earlier quoted context omitted.

You're just wrong. You're looking at the wrong numbers. The perplexity score of a model with twice the parameters in half the bits (4bit) is FAR LOWER (ie better). If you are limited to X RAM and have two 16bit models of size 4X and 2X then the 4X model in 4bit will always be far superior to the 2X model in 8bit, with far lower perplexity. Compare 13B's 4bit perplexity of 5.3607 to 7B's 8bit perplexity of 5.9069. Tha…

A stupid question but...what about a 16x model in 1bit?

Has binary neural network been implemented for Transformers yet?

Re: Numbers every LLM developer should know

#79
post #15

I would add the following two numbers if you're generating realtime text or speech for human consumption: - Human Reading Speed (English): ~250 words per minute - Human Speaking Speed (English): ~150 words per minute Should be treated like the Doherty Threshold [1] for generative content. [1] https://lawsofux.com/doherty-threshold/

But I'd say LLMs produce content faster than I can read or write it, because they can produce content which is really dense. Ask GPT-4 a question and then answer it yourself. Maybe your answer will be as good or better than GPT-4's but GPT-4 writes its answer a lot faster.

dense content? Not in my experience. It seems to be really overly verbose for me.

Re: Numbers every LLM developer should know

#80
post #34
post #31

Earlier quoted context omitted.

Vicuna-13b is on Apache License 2.0.

Vicuna is a delta model that you have to apply on top of LLaMA.

how does one get the original LLaMA weights. I tried the form that Meta has no dice. Also tried some torrents no luck there either
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