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Cerebras Inference: AI at Instant Speed

cerebras.ai

21–30 of 75 posts

Re: Cerebras Inference: AI at Instant Speed

#21

Can really fast inference (e.g. 1M tok/sec) make LLMs more intelligent? I am imagining you could run multiple agents and can choose and discard outputs using other LLMs simultaneously. Will the output look more like a real thought process? Or will it remain just same?

Fast inference can substitute for larger models in some circumstances. As you said, you can run multiple times. DeepMind had a detailed look, see https://arxiv.org/abs/2408.03314.

Re: Cerebras Inference: AI at Instant Speed

#22
post #9
post #6

Earlier quoted context omitted.

Cheaper on a per token basis.

Doubtful. SRAM is not cheap, and this is entirely about SRAM vs HBM.

They list the price in this press release. So either they're taking a big loss or they're doing it cheaper per token.

Re: Cerebras Inference: AI at Instant Speed

#23

Earlier quoted context omitted.

Cerebras' Wafer Scale Engine is the opposite of small and cheap. https://cerebras.ai/product-chip/

That's totally nuts. How do they deal with the silicon warping around disabled cores or dark silicon? How long of hard running does it take before the chip gets fatally damaged and needs to be replaced in their system? Word on the street is that h100s fail surprisingly often, this can't be better

https://www.youtube.com/watch?v=7GV_OdqzmIU&t=1104s

This video from Cerebras perfectly explain how they solve the interconnect problem, and why their approach greatly reduces the risk of Blackwell-type hardware design challenges.

Re: Cerebras Inference: AI at Instant Speed

#24

Earlier quoted context omitted.

Cerebras' Wafer Scale Engine is the opposite of small and cheap. https://cerebras.ai/product-chip/

That's totally nuts. How do they deal with the silicon warping around disabled cores or dark silicon? How long of hard running does it take before the chip gets fatally damaged and needs to be replaced in their system? Word on the street is that h100s fail surprisingly often, this can't be better

They have a way of bypassing bad cores, and over-provision both logic and memory by 1.5% to account for that. They get 100% yields this way.

https://www.anandtech.com/show/16626/cerebras-unveils-wafer-...

Re: Cerebras Inference: AI at Instant Speed

#25
post #6
post #4

Earlier quoted context omitted.

"wafer scale" inference using 44GB of straight up SRAM per chip does not exactly sound "smaller and cheaper" to me. Just optimized.

Cheaper on a per token basis.

I accept that. Your original comment left me under the impression that this represented a shift closer to the edge (I still don't think the hardware is all that much smaller), but I'll agree this is cheaper per token under full utilization.

Re: Cerebras Inference: AI at Instant Speed

#26
post #10

I want to know what the current power requirements are, as well as the cost for the machine. The last time I looked at one of these it was an absolute beast (although very impressive).

> I want to know what the current power requirements are, as well as the cost for the machine.

"If you care and have to ask it's not for you".

In all seriousness I've worked with and am familiar with Cerebras, Groq, etc. Let's just say GPUs still reign supreme in terms of practicality outside of usage of their hardware via cloud for nearly all use-cases.

Groq, for example, has essentially stopped selling their "real" HW directly because the borderline absurd amount of floor space, etc was found to be challenging once they hit the market. There's enough demand and more (recurring) money to be made anyway hosting services on your chips.

Similar to the Bitcoin mining ASIC game in the heyday - sure we could sell these or we could just use them to mine, develop next gen, sell previous gen, repeat.

Re: Cerebras Inference: AI at Instant Speed

#27

Earlier quoted context omitted.

Cerebras' Wafer Scale Engine is the opposite of small and cheap. https://cerebras.ai/product-chip/

That's totally nuts. How do they deal with the silicon warping around disabled cores or dark silicon? How long of hard running does it take before the chip gets fatally damaged and needs to be replaced in their system? Word on the street is that h100s fail surprisingly often, this can't be better

The way it's mounted, there's unlikely to be warping: https://web.archive.org/web/20230812020202/https://www.youtu...

The cooling is significantly better than what you'd see on a server platform with water cooling channels going to each row of the wafer.

Re: Cerebras Inference: AI at Instant Speed

#28
post #13

It would be understandable that they are focused currently on inference speed, but features like structured output and prompt caching make it possible to build more capable LLM applications. Does Cerebras support reliable structured output like the recent OpenAI 4o?

This question is a bit out of context. Cerebras is a startup producing innovative AI chips. Their chips are super cool, and I personally believe Cerebras is ahead of the industry and is on the right technical path. As a matter of fact, Cerebras started with HPC chips. Then pivoted to AI like everyone else. They are still deep in the trench for survival. Given that, they have very little software prowess compared to A…

As OpenAI themselves admits, structured output feature in question was developed in open source world first with zero funding.

Re: Cerebras Inference: AI at Instant Speed

#29
post #16

Sure but can they fit a bigger model? I don’t think they can string together these to fit bigger models like llama3.1 405b

https://youtu.be/re4QqXPmfgs?t=956

CS-3 system is built for single node domain scaling to 24 Trillion parameter models. I.e., they claim you can run the same code without hand-written distributed training code to reach 24 Trillion parameter models.

Re: Cerebras Inference: AI at Instant Speed

#30

Earlier quoted context omitted.

That's totally nuts. How do they deal with the silicon warping around disabled cores or dark silicon? How long of hard running does it take before the chip gets fatally damaged and needs to be replaced in their system? Word on the street is that h100s fail surprisingly often, this can't be better

They have a way of bypassing bad cores, and over-provision both logic and memory by 1.5% to account for that. They get 100% yields this way. https://www.anandtech.com/show/16626/cerebras-unveils-wafer-...

Yes,that's exactly what would cause the problems I'm suggesting.
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