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Calculating the cost of a Google DeepMind paper

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Re: Calculating the cost of a Google DeepMind paper

#71
post #10

Earlier quoted context omitted.

In principle, for some other company, sure. Google makes ~$300b a year in profit . They could make a $10m mistake every day and barely make a dent in it.

They do not, they made ~90 billion in profit. So no one would notice a 10 mil mistake, but no they didn't make 300b in profits.

I misread some stats, thanks for the correction.

Re: Calculating the cost of a Google DeepMind paper

#72
post #50
post #40

3USD/hour on the H100 is much more expensive than a reasonable amortized full ownership cost, unless one assumes the GPU is useless within 18 months, which I find a bit dramatic. The MFU can be above 40% and certainly well above the 35% in the estimate, also for small models with plain pytorch and trivial tuning [1] I didnt read the linked paper carefully but I seriously doubt the google team used vocab embedding lay…

You are correct on true H100 ownership costs being far lower. As I mention in the H100 blurb, the H100 numbers are fungible and I don't mind if you halve them. MFU can certainly be improved beyond 40%, as I mention. But on the point of small models specifically: the paper uses FSDP for all models, and I believe a rigorous experiment should not vary sharding strategy due to numerical differences. FSDP2 on small models…

I think the commenter was thinking about the input embedding layer, where to get an input token embedding the model does a lookup of the embedding by index, which is constant time.

And the blog post author is talking about the output layer where the model has to produce an output prediction for every possible token in the vocabulary. Each output token prediction is a dot-product between the transformer hidden state (D) and the token embedding (D) (whether shared with input or not) for all tokens in the vocabulary (V). That's where the VD comes from.

It would be great to clarify this in the blog post to make it more accessible but I understand that there is a tradeoff.

Re: Calculating the cost of a Google DeepMind paper

#73
post #24

Earlier quoted context omitted.

This assumes the common resources (CPU, RAM, etc.), not the ones required for the LLM training (GPU, TPU, etc.). It's different economy. TL; DR: It's not ~free.

Why does GPU matter? Do you think GCP keeps GPU utilization at 100% at all times?

What the OP is referring to requires overprovisioning of the high priority traffic and the sine-like utilization (without it, the benefits of the "batch" tier is close to zero -- the preemption is too high for any meaningful work when you are close to the top of the utilization hill).

You get that organically when you are serving lots of users. And, there's not much GPUs etc. used for that. Training LLMs gives you a different utilization pattern. The "best effort" resources aren't as useful in that setup.

Re: Calculating the cost of a Google DeepMind paper

#74

A lot of misunderstandings among the commenters here. From the link: "the total compute cost it would take to replicate the paper" It's not Google's cost. Google's cost is of course entirely different. It's the cost for the author if he were to rent the resources to replicate the paper. For Google, all of it is running at a "best effort" resource tier, grabbing available resources when not requested by higher priorit…

Is it free-priority based?

I was told by an employee that GDM internally has a credits system for TPU allocation, with which researchers have to budget out their compute usage. I may have completely misunderstood what they were describing, though.

Re: Calculating the cost of a Google DeepMind paper

#75
post #25
post #5

If this ran on google's own cloud it amounts to internal bookkeeping. The only cost is then the electricity and used capacity. Not consumer pricing. So negligible. It is rather unfortunate that this sort of paper is hard to reproduce. That is a BIG downside, because it makes the result unreliable. They invested effort and money in getting an unreliable result. But perhaps other research will corroborate. Or it may gi…

Opportunity cost is cost. What you could have earned by selling the resources to customers instead of using them yourself is what the resources are worth.

I think Google produces their own power, so they don’t pay distribution cost which is at least one third of the price of power, even higher for large customers.

Re: Calculating the cost of a Google DeepMind paper

#76

A lot of misunderstandings among the commenters here. From the link: "the total compute cost it would take to replicate the paper" It's not Google's cost. Google's cost is of course entirely different. It's the cost for the author if he were to rent the resources to replicate the paper. For Google, all of it is running at a "best effort" resource tier, grabbing available resources when not requested by higher priorit…

[deleted]

Re: Calculating the cost of a Google DeepMind paper

#78

A lot of misunderstandings among the commenters here. From the link: "the total compute cost it would take to replicate the paper" It's not Google's cost. Google's cost is of course entirely different. It's the cost for the author if he were to rent the resources to replicate the paper. For Google, all of it is running at a "best effort" resource tier, grabbing available resources when not requested by higher priorit…

According to neoclassical economists this is impossible since you can easily and instantaneously scale infrastructure up and down continuously at no cost and the future is known so demand can be predicted reliably. The problem with neoclassical economics is that it doesn't concern itself with the physical counterpart of liquidity. It is assumed that the physical world is just as liquid as the monetary world. The "liq…

> I would even go as far as to say that the production of liquidity is probably the driving force of the economy.

Isn't that all what high frequency traders would say? :)

Perhaps there is some limit at which additional liquidity doesn't offer much value?

Re: Calculating the cost of a Google DeepMind paper

#79

that's not very much in the business range, it's a lot when it comes to paying us salaries.

Any company of any size that doesn't learn the right lessons from a $10M mistake will be out of business before long.

I'm not really certain that's true at Google's size. Their annual revenue is something like a quarter trillion dollars. 25,000x larger than a $10m mistake.

The equivalent wastage for a self-employed person would be allowing a few cups of Starbucks coffee per year to go cold.

Re: Calculating the cost of a Google DeepMind paper

#80
post #5

If this ran on google's own cloud it amounts to internal bookkeeping. The only cost is then the electricity and used capacity. Not consumer pricing. So negligible. It is rather unfortunate that this sort of paper is hard to reproduce. That is a BIG downside, because it makes the result unreliable. They invested effort and money in getting an unreliable result. But perhaps other research will corroborate. Or it may gi…

> They chose to publish. So they are interested in seeing it reproduced or improved upon. Call me cynical, but this is not what I experienced to be the #1 reason of publishing AI papers.

I hope someone could share their insight on this comment. I think the other comments are fragile and don't hold too strongly.
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