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DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

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Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#71

Earlier quoted context omitted.

It's both compute and bandwidth constrained - just like trying to run Crysis on CPU rendering. A770 has 16GB of RAM. You're shuffling data to the GPU at a rate of 64GB/s, which is magnitudes slower than the internal VRAM of the GPU. Hence, this setup is memory bandwidth constrained. However, once you want to use it to do anything useful like a longer context size, the CPU compute will be a huge bottleneck for time-to…

Okay, let's stipulate LLMs are compute and bandwidth sensitive (of course!)... #1, should highlight it up front this time: We are talking about _G_PUs :) #2 You can't get a single consumer GPU that has enough memory to load a 670B parameter model, there's some magic going on here. It's notable and distinct. This is probably due to FlashMoE, given it's prominence in the link. TL;Dr: 1) these are Intel _G_PUs, and 2) i…

1) This system mostly uses normal DDR RAM, not GPU VRAM.

2) M3 Ultra can load Deepseek R1 671B Q4.

Using a very large LLM across the CPU and GPU is not new. It's been done since the beginning of local LLMs.

Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#72
post #59

As other commenters have mentioned, the performance of this set up is probably not really great since there's not enough VRAM and lots of bits have to be moved between CPU and GPU RAM. That said, there are sub-256GB quants of DeepSeek-R1 out there (not the distilled versions). See https://unsloth.ai/blog/deepseekr1-dynamic I can't quantify the difference between these and the full FP8 versions of DSR1, but I've been…

I tried that Unsloth R1 quantization on my dual Xeon Gold 5218 with 384 GB DDR4-2666 (about half of memory channels used, so not most optimal).

Type IQ2_XXS / 183GB, 16k context:

CPU only: 3 t/s (tokens per second) for PP (prompt processing) and 1.44 t/s for response.

CPU + NVIDIA RTX 70GB VRAM: 4.74 t/s for PP and 1.87 t/s for response.

I wish Unsloth produce similar quantization for DeepSeek V3, - it will be more useful, as it doesn't need reasoning tokens, so even with same t/s it will faster overall.

Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#73

Earlier quoted context omitted.

Also see the demo from Jason Dai's post: https://www.linkedin.com/posts/jasondai_with-the-latest-ipex...

CPU inference is both bandwidth and compute constrained. If your prompt has 10 tokens, it’ll do ok, like in the LinkedIn demo. If you need to increase the context, compute bottleneck will kick in quickly.

Prompt length mainly impacts prefill latency (FTFF), not the decoding speed (TPOT)

Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#74

What exactly does the Xeon do in this situation, is there a reason you couldn't use any other x86 processor?

  DDR4 UDIMM is up to 32GB/module  
  DDR5 UDIMM is up to 64GB/module[0]  
  non-Xeon M/B has up to 4 UDIMM slots 
  -> non-Xeon is up to 128GB/256GB per node  
Server motherboards have as many as 16 DIMM slots per socket with RDIMM/LRDIMM support, which allows more modules as well as higher capacity modules to be installed.

0: there has been a 128GB UDIMM launch at peak COVID

Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#75

What exactly does the Xeon do in this situation, is there a reason you couldn't use any other x86 processor?

There's not much else (other than Epyc) in the way of affordably priced motherboards that have enough cumulative RAM. You can buy a used Dell dual socket older xeon CPU server with 512GB of RAM for test/development purposes for not very much money. Under $1500 (before adding video cards or your own SSD), easily, with what I just found in a few minutes of searching. I'm also seeing things with 1024GB of RAM for under…

PowerEdge R series is significantly cheaper if you already have an ear protection

Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#76

Earlier quoted context omitted.

I remember people trying to run the game Crysis using CPU rendering. They got it to run and move around. People did it for fun and the "cool" factor. But no one actually played the game that way. It's the same thing here. CPUs can run it but only as a gimmick.

> It's the same thing here. CPUs can run it but only as a gimmick. No, that's not true. I work on local inference code via llama.cpp, on both GPU and CPU on every platform, and the bottleneck is much more ram / bandwidth than compute. Crappy Pixel Fold 2022 mid-range Android CPU gets you roughly same speed as 2024 Apple iPhone GPU, with Metal acceleration that dozens of very smart people hack on. Additionally, and pe…

> Crappy Pixel Fold 2022 mid-range Android CPU

Can you share what LLMs do you run on such small devices/what user case they address?

(Not a rhetorical question, it's just that I see a lot of work on local inference for edge devices with small models, but I could never get a small model to work for me. So I'm curious about other people's user cases.)

Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#78

Better to run the Q8 model on an epyc pair with 768GB, you'll get the same performance

The Q8 model is totally different?

My experience with quantizations is that anything below 6 is noticeably worse. Coherence suffers. I’ve rarely gotten anything really useful out of a Q4 model, code wise. For transformations they are great though, eg convert JSON to Markdown and vice versa.

Re: DeepSeek-R1-671B-Q4_K_M with 1 or 2 Arc A770 on Xeon

#80
post #77

Now we just need a model that can actually code

I'll settle with a much lower bar: an engineer that can tell the code the model generates is shit.

Most engineers can do that because it's way easier to find flaws in code you didn't write vs in ones that you write.

My code is always perfect in my own eyes until someone else sees it.

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