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TurboQuant: Redefining AI efficiency with extreme compression

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Re: TurboQuant: Redefining AI efficiency with extreme compression

#81

This is a great development for KV cache compression. I did notice a missing citation in the related works regarding the core mathematical mechanism, though. The foundational technique of applying a geometric rotation prior to extreme quantization, specifically for managing the high-dimensional geometry and enabling proper bias correction, was introduced in our NeurIPS 2021 paper, "DRIVE" ( https://proceedings.neurip…

If they didn't cite your paper that's bullshit. But if they read your paper enough that they invited you to a talk, that probably means they were far enough along to independently inventing it they were going to do so anyway, and wanted to chat with someone who was also doing the thing they were already doing. Good ideas tend to reveal themselves to anyone who is aware of the problem.

Doesn't matter, you should still cite. It's basic manners in science.

Re: TurboQuant: Redefining AI efficiency with extreme compression

#82
post #35
post #30

Pied Piper vibes. As far as I can tell, this algorithm is hardly compatible with modern GPU architectures. My guess is that’s why the paper reports accuracy-vs-space, but conveniently avoids reporting inference wall-clock time. The baseline numbers also look seriously underreported. “several orders of magnitude” speedups for vector search? Really? anyone has actually reproduced these results?

Classic academic move. If the authors show accuracy-vs-space charts but hide end-to-end latency, it usually means their code is slower in practice than vanilla fp16 without any compression. Polar coordinates are absolute poison for parallel GPU compute

I don't think they're using polar coordinates? They're quantizing to grid centroids.

Re: TurboQuant: Redefining AI efficiency with extreme compression

#83
post #36
post #28

Sounds like Multi-Head Latent Attention (MLA) from DeepSeek

Nah, those are completely different beasts. DeepSeek's MLA solves the KV cache issue via low-rank projection - they literally squeeze the matrix through a latent vector at train time. TurboQuant is just Post-Training Quantization where they mathematically compress existing weights and activations using polar coordinates

No, it is about compressing the KV cache; see How TurboQuant works.

Re: TurboQuant: Redefining AI efficiency with extreme compression

#84
post #30

Pied Piper vibes. As far as I can tell, this algorithm is hardly compatible with modern GPU architectures. My guess is that’s why the paper reports accuracy-vs-space, but conveniently avoids reporting inference wall-clock time. The baseline numbers also look seriously underreported. “several orders of magnitude” speedups for vector search? Really? anyone has actually reproduced these results?

Efficient execution on the GPU appears to have been one of the specific aims of the authors. Table 2 of their paper shows real world performance that would appear at a glance to be compatible with inference.

This is not an LLM inference result. Table 2 is the part I find most questionable. Claiming orders-of-magnitude improvements in vector search over standard methods is an extraordinary claim. If it actually held up in practice, I would have expected to see independent reproductions or real-world adoption by now. It’s been about a year since the paper came out, and I haven’t seen much of either. That doesn’t prove the claim is false, but it certainly doesn’t inspire confidence.

Re: TurboQuant: Redefining AI efficiency with extreme compression

#86

Earlier quoted context omitted.

I also instinctively reacted to that fragment, but at this point I think this is overreacting to a single expression. It's not just a normal thing to say in English, it's something people have been saying for a long time before LLMs existed.

There are tells all over the page: > Redefining AI efficiency with extreme compression "Redefine" is a favorite word of AI. Honestly no need to read further. > the key-value cache, a high-speed "digital cheat sheet" that stores frequently used information under simple labels No competent engineer would describe a cache as a "cheat sheet". Cheat sheets are static, but caches dynamically update during execution. Studen…

"The X Trick" or "The Y Dilemma" or similar snowclones in a header is also a big AI thing. Humans use this construction too, but LLMs love it out of all proportion. I call it The Ludlum Delusion (since that's how every Robert Ludlum book is titled).

Re: TurboQuant: Redefining AI efficiency with extreme compression

#87
Is this a tradeoff between GPU-computation-expense vs accuracy? ie: you could quantize into segments or grids on the unit circle/sphere/etc, but that's too expensive so it's better to just quantize to a Cartesian grid because the GPU can decompress cheaper?

Re: TurboQuant: Redefining AI efficiency with extreme compression

#88
This sounds great! TurboQuant does KV cache compression using quantization via rotations, and ParoQuant [1] does weight compression using quantization via rotations! So we can get 4-bit weights that match bf16 precision, the KV cache goes down to 3 bits per key. This brings larger models and long contexts into the range of "possibly runnable" on beefy consumer hardware.

[1] https://github.com/z-lab/paroquant

Re: TurboQuant: Redefining AI efficiency with extreme compression

#89

Can someone ELI5 these two concepts please, which make no sense to me: > "TurboQuant starts by randomly rotating the data vectors. This clever step simplifies the data's geometry" I don't understand how taking a series of data and applying a random rotation could mathemetically lead every time to "simpler" geometry. If I throw a bunch of shapes on the ground, tightly packed and touching each other, then rotate all of…

They are not doing random rotation, simplification here means they are aligning the outliers. If you threw a bunch of shapes on the ground they are picking up one that rolled away and putting it with the others.

>How can a boolean value preserve all of the relational and positional information between data points?

They aren't reducing entire vector to a bollean only each of its dimensions.

Re: TurboQuant: Redefining AI efficiency with extreme compression

#90

Can someone ELI5 these two concepts please, which make no sense to me: > "TurboQuant starts by randomly rotating the data vectors. This clever step simplifies the data's geometry" I don't understand how taking a series of data and applying a random rotation could mathemetically lead every time to "simpler" geometry. If I throw a bunch of shapes on the ground, tightly packed and touching each other, then rotate all of…

They are saying that models should be invariant to data's orientation - and only sensitive to the distance between vectors. This has a pretty significant effect on reducing the set of possible models, and may stabilize the optimization.

In simple terms, large ML models like LLMs often learn trivial rules such as "if the 21st decimal place of the 5th dimension in the embedding vector is 5 - then the image is of a cat." Learning such a memorization function is usually not what we are trying to do, and there are a variety of techniques to avoid these trivial solutions and "smooth" the optimization geometry.

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