arXiv AI

E8 Lattice Key Quantization for Low-Bit KV-Cache Compression

arXiv Machine Learning
1d ago

OScaR: The Occam's Razor for Extreme KV Cache Quantization in LLMs and Beyond

arXiv:2605.19660v3 Announce Type: replace Abstract: The rapid advancement toward long-context reasoning and multi-modal intelligence has made the memory footprint of the Key-Value (KV) cache a domina...

By Zunhai Su, Rui Yang, Chao Zhang, Yaxiu Liu, Yifan Zhang, Wei Wu, Jing Xiong, Dayou Du, Xialie Zhuang, Yulei Qian, Jianchao Tan, Yuchen Xie, Yik-Chung Wu, Hongxia Yang, Ngai Wong
arXiv Machine Learning
1d ago

PN-Mix: Pair-Norm Guided Mixed-Precision Key Cache Quantization for Efficient Long-Output LLM Inference

PN-Mix is a mixed‑precision key‑cache quantization technique for RoPE‑based decoder‑only large language models that allocates higher precision to salient channel pairs identified during the prefill stage. By focusing on channel pairs with large query–key pair‑norm products, PN‑Mix reduces logit variation caused by quantization errors. Experiments on reasoning, code‑generation, and AIME benchmarks show that PN‑Mix achieves comparable or better accuracy than prior methods while using an average precision of 2.26 bits and degrades gracefully down to 1.5 bits.

By Gil Jae Song, Sungjoo Yoo
Hugging Face Trending Papers
3d ago

MultiAlloc: Budget-Aware Precision Allocation for KV Cache Quantization

MultiAlloc is a profiling‑guided framework that allocates limited quantization resources between layer‑wise precision enhancement and token‑wise preservation for KV cache quantization in large language models. By using lightweight offline profiling to assess layer sensitivity and token importance, it automatically derives an effective precision allocation strategy that satisfies a fixed memory budget without online search. Experiments on reasoning and long‑context benchmarks show that MultiAlloc consistently outperforms existing layer‑wise, token‑wise, and multi‑granularity quantization methods across models such as Mistral, Llama, DeepSeek‑Qwen, and QwQ.

arXiv Machine Learning
Sep 25

A JoLT for the KV cache: Near-Lossless KV Cache Compression via Joint Rank-bit Allocation

The paper introduces JoLT, a training‑free compressor that jointly allocates rank and precision for key‑value (KV) cache compression in long‑context language models. JoLT treats grouped prefill caches as fourth‑order tensors, applies partial Tucker decomposition along token and feature modes, and uses a rotated low‑bit quantizer for residuals, all governed by a single Lagrangian dual under a global byte constraint. Across five models from four architecture families, JoLT achieves 2–3× compression with less than 0.2% perplexity loss, and near‑lossless retrieval accuracy on LLaMA‑3.1‑8B at 64K context up to 3× compression.

By Rahul Krishnan, Volker Schulz
arXiv Machine Learning
Oct 8

Dual-QK: Sharp Queries and Flat Keys for Prunable 2-bit KV Caches

Dual-QK introduces paired non‑orthogonal transforms for queries and keys to enable sharp queries and flat keys, improving 2‑bit quantization and dynamic channel pruning of KV caches. The method balances key scales for INT2 quantization while concentrating query energy for pruning, and supports channel‑0 protection and bucket‑relative RoPE for long‑context accuracy. Experiments on four models across five generative benchmarks show that Dual‑QK outperforms OSCAR at 40% query‑channel sparsity, achieving 6.8× KV‑cache compression, an 8.3× reduction in KV read volume, and up to 3.75× decoding throughput over unpruned BF16.

By Sunjoo Whang, Jungjun Oh, Minsung Kim, Dongho Seo, Jisu Shin, Gregory Kielian, Hoi-Jun Yoo, Sangjin Kim
arXiv Computation and Language
Sep 18

D-Quant: Driftable Entropy Coding for KV Cache Quantization

The paper introduces D-Quant, a KV cache quantization framework that addresses the memory bottleneck of large language models by using a drift mechanism to convert entropy-coded representations into fixed-size bitstreams. This approach leverages the non-uniform distribution of KV cache values—after rotation and normalization, they approximate a normal distribution—allowing entropy coding to assign shorter codewords to frequent symbols while maintaining regular memory layouts suitable for parallel attention kernels. D-Quant thus aims to reduce memory footprint and bandwidth usage without sacrificing performance.

By Yi Su, Hong Liu, Guanghua Yu, Jianchen Zhu