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llm inference optimization

SHOW HN2025

272points
40comments
#206of 3,837 in 2025
Top 6%of 2025 by points

How HN took it

CuriousMostly questions and neutral comments

2 positive, 18 neutral or asking, 0 mixed, 12 critical, out of 32 comments about the project. Thread score -0.21.

Idea: 1 for, 3 againstExecution: 0 for, 3 againstPerformance: 0 for, 2 againstPrivacy: 0 for, 1 against

The thread, comment by comment

Each row is a top-level comment and its replies, in HN's order. Select a cell to open that comment on HN.

positive neutral or mixed critical about another commenter or something else the maker

What HN said

What people liked

  • Interesting idea about asymmetric key/value precision

    From 2 comments
    • Great work. This seems very interesting, but I need something slightly more high level to relate to it Will it just allow me to run let’s say a model with a 2048 token context…
      nico on HN
    • This is a brilliant idea, and initiative. Does this also apply to GPUs? And I assume should be compatible with other quantization techniques, albeit they probably require their…
      3abiton on HN

Objections

  • Same functionality already exists via --cache-type-k and --cache-type-v flags

    From 4 comments
    • you can do this already with -ctk and -ctv, why would anyone need this? -ctk, --cache-type-k TYPE KV cache data type for K ``` allowed values: f32, f16, bf16, q8_0, q4_0, q4_1,…
      segmondy on HN
    • Am I missing something? As far as I can see this patch does nothing except add new options that replicate the functionality of the existing --cache-type-k and --cache-type-v…
      therealsmith on HN
    • > A note, your install script appears to still have a placeholder at the "apply patch" step. A suggestion, might be more user-friendly to fork llama.cpp and then include that as…
      Aurornis on HN
    • I finally had time to read the code. The patch is unnecessary because this functionality has been in llama.cpp since 2023 if I understand this PR correctly:…
      Aurornis on HN
  • Install script applies a patch that is unnecessary and looks suspicious

    From 3 comments
    • I finally had time to read the code. The patch is unnecessary because this functionality has been in llama.cpp since 2023 if I understand this PR correctly:…
      Aurornis on HN
    • > A note, your install script appears to still have a placeholder at the "apply patch" step. A suggestion, might be more user-friendly to fork llama.cpp and then include that as…
      Aurornis on HN
    • After looking more, this is definitely an AI driven attempt to game the system. It’s too bad the comments calling it out earlier were downvoted away. The first one was downvoted…
      Aurornis on HN
  • 0.86% perplexity loss is significant at short context

    From 2 comments
    • +0.86% perplexity it's quite a bit at such a small context size though isn't it? How is it at more reasonable context sizes like 64-128k?
      smcleod on HN
    • Yeah I get that, that's what we yse k/v cache quantisation for now which has a lower impact on PPL than this unless I'm missing something?
      smcleod on HN
  • Maker's GitHub activity looks like LLM-generated star farming

    From 2 comments
    • Finally someone making sense. The fact this project works by applying patches instead of forking the original project and committing changes should alone be reason for concern.…
      imiric on HN
    • After looking more, this is definitely an AI driven attempt to game the system. It’s too bad the comments calling it out earlier were downvoted away. The first one was downvoted…
      Aurornis on HN

Requests

  • Explain how this differs from existing cache-type flags

    From 2 comments
    • Is this any different from using --cache-type-k and --cache-type-v?
      ondra on HN
    • Is this any different from using --cache-type-k and --cache-type-v?
      hiatus on HN
  • Fork llama.cpp instead of patch-apply install script

    From 1 comment
    • Looks interesting! Is there any intuition for why this should be the case? Did you discover it via that intuition, or just random experimentation? A note, your install script…
      matheist on HN
  • Benchmarks at longer contexts such as 64-128K

    From 1 comment
    • +0.86% perplexity it's quite a bit at such a small context size though isn't it? How is it at more reasonable context sizes like 64-128k?
      smcleod on HN
  • Support for MLX

    From 1 comment
    • Is this patch possible to do on MLX? I'm getting better speeds on MLX. That, combined with your approach, would finally let Mac users have long conversations at usable speeds.
      behnamoh on HN

Questions

  • Does this work on GGUF models without conversion?

    From 1 comment
    • I'm curious: is it possible to apply differentiated KV quantization (like K8V4) to models after they're already converted to .gguf format, or does this require rebuilding the…
      badmonster on HN
  • Does it speed up generation or only save memory?

    From 2 comments
    • Amazing! Curious, what happens to performance? I assume you still pay the same performance price for longer context, even if you can now fit it in memory.
      zmmmmm on HN
    • Will that make the model run/feel faster? I can run models with 30-40b parameters on my computer, but they feel a lot slower than the 1-7b ones So would this make the 30-40b…
      nico on HN
  • Does it require flash attention?

    From 1 comment

Alternatives named

  • llama.cpp --cache-type-k and --cache-type-v flags

    From 2 comments
    • you can do this already with -ctk and -ctv, why would anyone need this? -ctk, --cache-type-k TYPE KV cache data type for K ``` allowed values: f32, f16, bf16, q8_0, q4_0, q4_1,…
      segmondy on HN
    • Am I missing something? As far as I can see this patch does nothing except add new options that replicate the functionality of the existing --cache-type-k and --cache-type-v…
      therealsmith on HN
  • MLX

    From 1 comment
    • Is this patch possible to do on MLX? I'm getting better speeds on MLX. That, combined with your approach, would finally let Mac users have long conversations at usable speeds.
      behnamoh on HN

Category, keywords, summaries and labels on this page were made by AI (Thread Reader v2) and not checked by hand. Each point links to the comments it came from.

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