arXiv AI

WAKMan: Workload Aware KVCache Manager

WAKMan is a workload‑aware KV cache manager designed for Large Language Model servers that selects an eviction policy based on live traffic patterns without needing to know request types or read prompts. By adapting to the mix of single‑turn, multi‑turn, and agentic requests, it improves cache hit rates over the default LRU strategy by an average of 5 percentage points and achieves the lowest mean and worst‑case optimality gap among evaluated policies. The paper demonstrates that no single policy consistently outperforms others across diverse traffic mixes, highlighting the need for dynamic, workload‑aware cache management.

arXiv Computation and Language
Oct 21

Cache Engineering for Agents

The paper introduces cache engineering for large language model agents, enabling direct control over the active key-value cache without altering the trajectory or triggering costly re-prefilling. It defines cache operations such as drop and repos, formalizes their effects, and addresses the challenge of history-dependent cache states. The authors co-design a stateless AKV serving engine that manages stateful cache reuse, eviction, and restoration, achieving significant performance and cost improvements over traditional summarization methods.

By Tianyu Fu, Ruoxi Wang, Zihan Min, Zhongqi Ren, Zhihao Li, Tengxuan Liu, Shengxu Mu, Hanling Zhang, Yu Wang
arXiv Machine Learning
Aug 10

Cascade: Exploiting SLO-Aware latency budget for fair and high goodput LLM inference serving

arXiv:2608. 06557v1 Announce Type: cross Abstract: The reasoning and agentic capabilities of large language models have expanded the range of applications they support, from short interactive exchanges to long, compute-heavy requests.

By Muhammad Adnan, Rohan Mahapatra, Prashant J. Nair, Daniel Berger, Pantea Zardoshti, Rodrigo Fonseca, Esha Choukse
arXiv Machine Learning
Sep 25

When Fancy Eviction Fails: Rethinking Cache Replacement For LLM Prefix Reuse

The paper investigates cache replacement strategies for large language model (LLM) prefix reuse, analyzing production traces from two companies and testing 14 eviction algorithms in both high-bandwidth memory (HBM) and large memory-pool environments. It finds that sophisticated policies designed for traditional caches offer little advantage over simple LRU, because prefix reuse is largely driven by the regular pacing of active sessions, making recency a strong predictor. The study also highlights new challenges such as heavy-tailed session footprints and variable miss costs, and proposes a compute-savings ratio along with two offline oracles to better quantify these effects, suggesting that effective prefix-cache management should combine recency with selective quick demotion, compute-aware partial eviction, and capacity-dependent granularity.

By Yiyu Liu, Minlan Yu, Juncheng Yang
arXiv Computation and Language
Aug 27

TOPAS: Workflow-Aware Prefix-State Scheduling for Multi-Agent LLM Serving

TOPAS is a Task‑Oriented Prefix‑Aware Scheduler designed for multi‑agent large language model serving. It jointly decides which agent prefixes to retain in a shared key‑value cache and which requests to schedule, balancing the reduction of each task’s longest remaining service path against the benefit of downstream prefix reuse while accounting for movement and preemption costs. Experiments on synthetic DAGs and MetaGPT software‑development workflows show that TOPAS can reduce mean and p99 job completion times by up to 39.8%/49.4% and 22.0%/26.6% respectively compared to the best baselines.

By Hongqiu Ni, Han Tian, Chi Zhang, Guopeng Li, Haisheng Tan