DolphinRouting：面向解耦式LLM推理服务的集群级二元路由
DolphinRouting: Cluster-Level Binary Routing for Disaggregated LLM Inference Serving
Yishuo Yuan, Shaoyu Yang, Chunrong Fang
AI 速览：DolphinRouting 按请求特征聚类，并用离线策略搜索为每个簇学习一个二元路由决策，从而在 PD 解耦集群中选择本地或远程 prefill。
Prefill-decode (PD) disaggregation isolates the two phases of large language model serving, but request-level path selection must account for prefill work, cache reuse, and decode demand. We present DolphinRouting, which learns this choice from end-to-end SLO feedback under a given P/D resource allocation. Requests are clustered by raw prompt length, cache-adjusted input lengths on both worker pools, and output-length information. Offline policy search learns one binary action per cluster. Online feature extraction, cluster assignment, and table lookup select local or remote prefill. We evaluate DolphinRouting on a real PD-disaggregated cluster using three public benchmarks, a mixed workload, and real data. Across the mixed workload and real data, DolphinRouting with $k$-means reduces P90 TTFT by 5.7--7.9\% and P90 TPOT by 2.6--10.1\% relative to Dynamo.