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Groq runs Mixtral 8x7B-32k with 500 T/s

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Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#101
post #97
post #95

Earlier quoted context omitted.

They're using hundreds of chips. Based on the data sheet I would estimate this demo uses 173 KW. It may be 100x energy to get 10x speedup.

100s of chips for who knows how many clients. The mobile phone will have to do calculations just for 1 client.

Yes, we pipeline requests so multiple users are being handled by the same hardware at one time.

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#102
post #89
post #87

Earlier quoted context omitted.

The thing is, I don't see any efficiency improvements. I see models running fast on very expensive hardware using techniques that don't scale down.

Care to explain? Are they using 10x energy for 10x speed improvements?

I think the limitation is chip size/cost. SRAM is a lot less dense than RAM. According to Google this is typically used for registers and caches, which are only megabytes large.

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#103
post #91

The main problem with the Groq LPUs is, they don't have any HBM on them at all. Just a miniscule (230 MiB) [0] amount of ultra-fast SRAM (20x faster than HBM3, just to be clear). Which means you need ~256 LPUs (4 full server racks of compute, each unit on the rack contains 8x LPUs and there are 8x of those units on a single rack) just to serve a single model [1] where as you can get a single H200 (1/256 of the server…

If you want low latency you have to be really careful with HBM, not only because of the delay involved, but also the non-determinacy. One of the huge benefits of our LPU architecture is that we can build systems of hundreds of chips with fast interconnect and we know the precise timing of the whole system to within a few parts per million. Once you start integrating non-deterministic components your latency guarantee…

I don't know about HBM specifically, but DDR and GDDR at a protocol level are both deterministic. It's the memory controller doing a bunch of reordering that makes them non-deterministic. Presumably, if that is the reason you don't like DRAM, you could build your compiler to be memory-layout aware and have the memory controller issue commands without reordering.

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#104

Earlier quoted context omitted.

Groq Engineer here, I'm not seeing why being able to scale compute outside of a single card/node is somehow a problem. My preferred analogy is to a car factory: Yes, you could build a car with say only one or two drills, but a modern automated factory has hundreds of drills! With a single drill, you could probably build all sorts of cars, but a factory assembly line is only able to make specific cars in that configur…

Just curious, how does this work out in terms of TCO (even assuming the price of a Groq LPU is 0$)? What you say makes sense, but I'm wondering how you strike a balance between massive horizontal scaling vs vertical scaling. Sometimes (quite often in my experience) having a few beefy servers is much simpler/cheaper/faster than scaling horizontally across many small nodes. Or I got this completely wrong, and your solu…

We're providing by far the lowest latency LLM engine on the planet. You can't reduce latency by scaling horizontally.

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#105
post #41

Does this make it practical to run LLMs on mobile devices? I wonder about the power consumption and if it can make sense to have it integrated in some future mobile devices. Or maybe have a dedicated storage, RAM and processing cores that goes as an USB-C add-on? A case with integrated battery and this chip? I'm dreaming of having LLMs on anything. Unlike the "bluetooth on everything" craze, this can be practical as…

> Remember how some British researchers made a self driving car using an LLM?

No? Do you mean actual, full self driving on normal roads in traffic?

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#106

Very impressive looking! Just wanted to caution it's worth being a bit skeptical without benchmarks as there are a number of ways to cut corners. One prominent example is heavy model quantization, which speeds up the model at a cost of model quality. Otherwise I'd love to see LLM tok/s progress exactly like CPU instructions/s did a few decades ago.

At least for the earlier Llama 70B demo, they claimed to be running unquantized. https://twitter.com/lifebypixels/status/1757619926360096852

Update: This comment says "some data is stored as FP8 at rest" and I don't know what that means. https://news.ycombinator.com/item?id=39432025

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#107
post #98
post #88

Earlier quoted context omitted.

How does the Groq PCIE Card work exactly? Does it use system ram to stream the model data to the card? How many T/s could one expect with e.g. 36000Mhz DDR4 Ram?

We build out large systems where we stream in the model weights to the system once and then run multiple inferences on it. We don't really recommend streaming model weights repeatedly onto the chip because you'll lose the benefits of low latency.

How does that work when the card only has 230MB of SRAM?

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#109

The main problem with the Groq LPUs is, they don't have any HBM on them at all. Just a miniscule (230 MiB) [0] amount of ultra-fast SRAM (20x faster than HBM3, just to be clear). Which means you need ~256 LPUs (4 full server racks of compute, each unit on the rack contains 8x LPUs and there are 8x of those units on a single rack) just to serve a single model [1] where as you can get a single H200 (1/256 of the server…

>The main problem with the Groq LPUs is, they don't have any HBM on them at all. Just a miniscule (230 MiB) [0] amount of ultra-fast SRAM [...]

IDGAF about any of that, lol. I just want an API endpoint.

480 tokens/sec at $0.27 per million tokens? Sign me in, I don't care about their hardware, at all.

Re: Groq runs Mixtral 8x7B-32k with 500 T/s

#110
post #91

Earlier quoted context omitted.

If you want low latency you have to be really careful with HBM, not only because of the delay involved, but also the non-determinacy. One of the huge benefits of our LPU architecture is that we can build systems of hundreds of chips with fast interconnect and we know the precise timing of the whole system to within a few parts per million. Once you start integrating non-deterministic components your latency guarantee…

I don't know about HBM specifically, but DDR and GDDR at a protocol level are both deterministic. It's the memory controller doing a bunch of reordering that makes them non-deterministic. Presumably, if that is the reason you don't like DRAM, you could build your compiler to be memory-layout aware and have the memory controller issue commands without reordering.

That could be possible. It's out of my area of expertise so I can't say for sure. My understanding was HBM forces on you specific access patterns and non-deterministic delays. Our compiler already deals with many other forms of resource-aware scheduling so it could take into account DRAM refreshes easily, so I feel like there must be something else that makes SRAM more suitable in our case. I'll have to leave that to someone more knowledgeable to explain though ...
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