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Kaist develops next-generation ultra-low power LLM accelerator

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31–40 of 41 posts

Re: Kaist develops next-generation ultra-low power LLM accelerator

#31
post #29
post #17

Earlier quoted context omitted.

Only $5M then.

$5M once, upfront. But given the significantly increased throughput, how fast does that pay for itself?

Depends on power usage. I’m curious how power hungry those are compared to server/workstation cards.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#32
post #6

Want to reference Groq.com. They are developing their own inference hardware called an LPU https://wow.groq.com/lpu-inference-engine/ They also released their API a week or 2 ago. Its significantly faster than anything from OpenAI right now. Mixtral 8x7b operates at around 500 tokens per second. https://groq.com/

It's not so much an accelerator as it is addressing the main inference bottleneck (i.e. memory latency) with sheer brute force by throwing money at the problem. They've made accelerators out of pure L3 cache with a whopping 230 MB per card. They cited something like 500 cards to load one single Mixtral instance, which probably cost over $10M to build. It's a supercomputer essentially.

Grayskull has 96 MB SRAM and people call it overpriced at $600 to $800. It is far more plausible that their chip costs are somewhere around $500.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#33
post #22

Neuromorphic computing is cool, but not new tech. However, using a neuromorphic spiking architecture to run LLMs seems new. Unfortunately, there doesn't seem to be a paper associated with this work, so there's no deeper information on what exactly they're doing.

I heavily doubt that they are running LLMs on this.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#34
post #4
post #3

> New structure mimics the layout of neurons and synapses What does that mean, practically? How can you mimic that layout in silicon?

This means they use Spiking Neural Networks. It’s a software algorithm that most likely doesn’t work as well as regular NNs.

Spiking neural networks are not software, they are usually built directly into silicon chips because they are using pulse timing to encode information instead of multiple bits. The problem is that training them is difficult because they operate over time, not that they don't work. As of now, scaling training infrastructure is more important than theoretical power efficiency.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#36

Earlier quoted context omitted.

It's not so much an accelerator as it is addressing the main inference bottleneck (i.e. memory latency) with sheer brute force by throwing money at the problem. They've made accelerators out of pure L3 cache with a whopping 230 MB per card. They cited something like 500 cards to load one single Mixtral instance, which probably cost over $10M to build. It's a supercomputer essentially.

What's the cost per inference relative to H100? Isn't that the number to care about?

Based on some rough ballpark conservative estimates (one server with 2 A100 at $50000; 50 tokens/s one one of those servers; so 10 of those servers), upfront cost with consumer hardware seems to be 1/10 to 1/20 of what the Groq hardware costs. I would guess that realistically cloud providers can probably achieve half to 1/3 of that price

So unless you need the fast latency of Groq, consumer hardware seems to be a lot cheaper for the same thoughput.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#37
post #29
post #17

Earlier quoted context omitted.

Only $5M then.

$5M once, upfront. But given the significantly increased throughput, how fast does that pay for itself?

You need computers for all of them and megawatts of power, power supplies, cooling, and power distribution.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#38
post #17

Earlier quoted context omitted.

They need 568 LPUs to load both Mixtral 8x7B and LLaMA 70B, because they need both those models available for the demo. I imagine Mixtral by itself would only take something like 200-300 LPUs

Only $5M then.

I'm pretty sure $20,000 per LPU isn't actually the cost of these LPUs. I saw someone else on HN asking if $20,000 could get them something and an employee said to reach out. Which makes me think $20,000 is enough to get some sort of model running at least, even if it's not necessarily an LLM.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#39
post #22

Neuromorphic computing is cool, but not new tech. However, using a neuromorphic spiking architecture to run LLMs seems new. Unfortunately, there doesn't seem to be a paper associated with this work, so there's no deeper information on what exactly they're doing.

I heavily doubt that they are running LLMs on this.

The article says they ran GPT-2! Which isn't particularly large, but replicating a large language model with a spiking neural network seems like novel work at least.

Re: Kaist develops next-generation ultra-low power LLM accelerator

#40
post #37
post #29

Earlier quoted context omitted.

$5M once, upfront. But given the significantly increased throughput, how fast does that pay for itself?

You need computers for all of them and megawatts of power, power supplies, cooling, and power distribution.

Naturally, but you need that for GPUs as well, no? What is the actual difference when running, when measured per token generated?
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