LeanK: Learnable K Cache Channel Pruning for Efficient Decoding
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Abstract (arXiv)
Large language models (LLMs) enable long-context tasks but face efficiency challenges due to the growing key-value (KV) cache. We propose LeanK, a learning-based method that prunes unimportant key (K) cache channels by leveraging static channel sparsity. With a novel two-stage training process, LeanK learns channel-wise static mask that could satisfy specific sparsity ratio and hardware alignment requirement. LeanK reduces GPU memory and accelerates decoding without sacrificing accuracy. Experiments demonstrate up to 70% K cache and 16%-18% V cache memory reduction. Custom decoding kernel enables 1.3x speedup for attention computation. We also provide insights into model channels and attention heads during long-context inference by analyzing the learned importance distribution. Our code is available at https://aka.ms/LeanK.
Key facts. Cited by 7 papers in the map (data through 14 Oct 2026). Builds on 24 of its 31 references that are in the map. First posted on arXiv 4 Aug 2025.
Builds on
24 of 31 references.
References · 24
- 2014Adam: A Method for Stochastic Optimizationcited by 37,240
- 2023SWE-bench: Can Language Models Resolve Real-World GitHub Issues?cited by 3,373
- 2023Efficient Streaming Language Models with Attention Sinkscited by 2,186
- 2023LongBench: A Bilingual, Multitask Benchmark for Long Context Understandingcited by 1,417
- 2024RULER: What's the Real Context Size of Your Long-Context Language Models?cited by 1,346
- 2023SparseGPT: Massive Language Models Can Be Accurately Pruned in One-Shotcited by 1,121
- 2024SnapKV: LLM Knows What You are Looking for Before Generationcited by 880
- 2024KIVI: A Tuning-Free Asymmetric 2bit Quantization for KV Cachecited by 637
- 2024Quest: Query-Aware Sparsity for Efficient Long-Context LLM Inferencecited by 501
- 2024DuoAttention: Efficient Long-Context LLM Inference with Retrieval and Streaming Headscited by 288
- 2024Retrieval Head Mechanistically Explains Long-Context Factualitycited by 232
- 2024The Unreasonable Ineffectiveness of the Deeper Layerscited by 226
12 more
- 2023LooGLE: Can Long-Context Language Models Understand Long Contexts?cited by 202
- 2024A Survey on Recent Advances in LLM-Based Multi-turn Dialogue Systemscited by 170
- 2024Not All Experts are Equal: Efficient Expert Pruning and Skipping for Mixture-of-Experts Large Language Modelscited by 146
- 2023SparQ Attention: Bandwidth-Efficient LLM Inferencecited by 119
- 2024RetrievalAttention: Accelerating Long-Context LLM Inference via Vector Retrievalcited by 116
- 2024Round and Round We Go! What makes Rotary Positional Encodings useful?cited by 115
- 2024MagicPIG: LSH Sampling for Efficient LLM Generationcited by 111
- 2024ThinK: Thinner Key Cache by Query-Driven Pruningcited by 68
- 2024Post-Training Sparse Attention with Double Sparsitycited by 45
- 2025TileLang: A Composable Tiled Programming Model for AI Systemscited by 43
- 2025Quantization Meets Reasoning: Exploring LLM Low-Bit Quantization Degradation for Mathematical Reasoningcited by 37
- 2024On the token distance modeling ability of higher RoPE attention dimensioncited by 13
Built on by
Citing papers per year: 2025: 1; 2026: 6.
7 papers.
- 2026RAP: KV-Cache Compression via RoPE-Aligned Pruningcited by 3
- 2025The Structural Scalpel: Automated Contiguous Layer Pruning for Large Language Modelscited by 2
- 2026HieraSparse: Hierarchical Semi-Structured Sparse KV Attentioncited by 0
- 2026Rotation-Aligned Key Channel Pruning for Efficient Vision-Language Model Inferencecited by 0
- 2026S4R: Selective Sampling, Subspaces, and Sparse Reconstruction for Compressed Long-Context KV Cachingcited by 0
- 2026WavePrune: One period is often enough for RoPEcited by 0
- 2026PN-Mix: Pair-Norm Guided Mixed-Precision Key Cache Quantization for Efficient Long-Output LLM Inferencecited by 0
- 2026PN-Mix: Pair-Norm Guided Mixed-Precision Key Cache Quantization for Efficient Long-Output LLM Inference14 Oct 2026
- 2026WavePrune: One period is often enough for RoPE3 Oct 2026
- 2026S4R: Selective Sampling, Subspaces, and Sparse Reconstruction for Compressed Long-Context KV Caching1 Aug 2026
- 2026Rotation-Aligned Key Channel Pruning for Efficient Vision-Language Model Inference19 May 2026
- 2026HieraSparse: Hierarchical Semi-Structured Sparse KV Attention18 Apr 2026
- 2026RAP: KV-Cache Compression via RoPE-Aligned Pruning1 Feb 2026
- 2025The Structural Scalpel: Automated Contiguous Layer Pruning for Large Language Models25 Oct 2025