CacheRoute: Planned Prefix-Affinity Routing for Large-Scale LLM Serving
- URL: http://arxiv.org/abs/2608.19677v1
- Date: Thu, 20 Aug 2026 06:12:47 GMT
- Title: CacheRoute: Planned Prefix-Affinity Routing for Large-Scale LLM Serving
- Abstract summary: CacheRoute sustains 176 +/-11 QPS at a 3.5-s p99 SLO, 2.3x the strongest of five baselines.<n>On Llama-3.3-70B in fp8 across 60 H100 GPUs, CacheRoute sustains 176 +/-11 QPS at a 3.5-s p99 SLO, 2.3x the strongest of five baselines.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Prefix caching avoids prefill only when a repeated request returns to a server that still holds the prefix KV. Cache-blind balancing disperses that reuse; fixed affinity preserves it but can overload a server. CacheRoute resolves this tradeoff with a periodic routing plan. It admits high-rate keys to a stable warm set and places their assignments by expected load. Hot keys may use more than one destination, although every key in our primary semi-synthetic aggregate uses exactly one. On Llama-3.3-70B in fp8 across 60 H100 GPUs, CacheRoute sustains 176+/-11 QPS at a 3.5-s p99 SLO, 2.3x the strongest of five baselines. Served KV-cache hit rate rises from 64.1+/-1.3% under cache-blind balancing to 93.2+/-0.5%. A second semi-synthetic aggregate and controlled 8B and burst experiments separate the effects of affinity and placement. Two 32B workloads provide the counterexamples: when affinity recovers too little KV work, its residual load skew reduces or erases the improvement. We therefore recommend gating any deployment with a shadow replay rather than enabling affinity from workload statistics alone.
Related papers
- Same Request, Different Answer: Quantization Amplifies Cache-Induced Divergence in LLM Serving [0.0]
Prefix caching, in which a serving engine reuses the key and value tensors of a shared prompt prefix across requests, is enabled by default in the major open-source stacks.<n>We run an eighty-episode multi-turn agentic tool-use workload with caching enabled and disabled across two engines and four weight formats.<n>We find that repeated execution was bit-identical in every configuration, 0 of 800 episodes, which bounds other sources of nondeterminism at 0.5 percent.
arXiv Detail & Related papers (2026-09-04T05:27:34Z) - ReCache: Efficient KV Cache Reuse and Compression for Tool-Augmented LLM Agents [7.368551130048085]
textbfReCache is a framework for independently caching resource representations.<n>We evaluate ReCache on a benchmark assembled from seven public tool- and skill-use datasets.
arXiv Detail & Related papers (2026-08-20T05:57:24Z) - Governing the KV Cache: Preventing Timing Side-Channel Leakage in Multi-Tenant LLM Inference [0.0]
Key-value (KV) cache is the primary throughput optimization in modern large language model (LLM) inference.<n>Three published attacks exploit it, reaching up to 100% attack success rate against unprotected vLLM and SG.<n>We present KVGov, a governance layer addressing all three attack families' prefix-cache paths.
arXiv Detail & Related papers (2026-08-10T07:47:57Z) - Back from the Future: Key-Value Cache Management by Counter-Causal Surprise [67.1056509495879]
Key-value (KV) cache management through compression and eviction strategies has emerged as an important research direction in recent years.<n>We propose a simple yet effective KV eviction scheme motivated by the insight that past tokens which can be well-predicted from more recent tokens are redundant.<n>We evaluate our strategy on various open-source LLMs and benchmark datasets showing competitive or improved performance over other state-of-the-art methods.
arXiv Detail & Related papers (2026-07-30T02:42:51Z) - Cache-Aware Prompt Compression:A Two-Tier Cost Model for LLM API Caching [7.336436436266022]
We characterize the cost empirically on Anthropic's Sonnet 4.6 API.<n>We propose Cache-Aware Prompt Compression (CAPC)<n>CAPC is the cheapest strategy in 16/16 configurations on LongBench-v2.
arXiv Detail & Related papers (2026-07-17T00:03:47Z) - Grounded Cache Routing for Retrieval-Augmented Generation: When Is It Safe to Reuse an Answer? [0.0]
We propose GroundedCache, an evidence-validated cache router that admits a cached answer only when 4 cheap gates simultaneously hold.<n>We build a six-regime workload that stress-tests cache safety rather than only hit rate, and introduce an operator-facing metric, the unsafe-served rate (USR)<n>Across 2 datasets and 12,000 real-LLM generations(Qwen2.5-7B-Instruct on vLLM with Automatic Prefix Caching), GroundedCache drives USR to 0.0% on every HotpotQA regime and to 1.5% on mtRAG document drift.
arXiv Detail & Related papers (2026-05-26T16:50:02Z) - StepCache: Step-Level Reuse with Lightweight Verification and Selective Patching for LLM Serving [0.0]
We present StepCache, a backend-agnostic step-level reuse layer that segments outputs into ordered steps.<n>StepCache regenerates only failing regions via selective patching.<n>It reduces mean latency from 2.13 s to 0.67 s, median latency from 2.42 s to 0.01 s, and p95 latency from 3.38 s to 3.30 s.
arXiv Detail & Related papers (2026-03-24T17:19:26Z) - PackCache: A Training-Free Acceleration Method for Unified Autoregressive Video Generation via Compact KV-Cache [61.57938553036056]
We introduce PackCache, a training-free KV-cache management method that compacts the KV cache through three coordinated mechanisms.<n>In terms of efficiency, PackCache accelerates end-to-end generation by 1.7-2.2x on 48-frame long sequences.
arXiv Detail & Related papers (2026-01-07T19:51:06Z) - R-KV: Redundancy-aware KV Cache Compression for Reasoning Models [77.84539432982307]
We propose Redundancy-aware KV Cache Compression for Reasoning models (R-KV)<n>R-KV preserves nearly 100% of the full KV cache performance using only 10% of the KV cache.<n>Remarkably, R-KV even achieves 105% of full KV cache performance with 16% of the KV cache.
arXiv Detail & Related papers (2025-05-30T02:03:24Z) - vCache: Verified Semantic Prompt Caching [95.16654660556975]
This paper proposes vCache, the first verified semantic cache with user-defined error rate guarantees.<n>It employs an online learning algorithm to estimate an optimal threshold for each cached prompt, enabling reliable cache responses without additional training.<n>Our experiments show that vCache consistently meets the specified error bounds while outperforming state-of-the-art static-threshold and fine-tuned embedding baselines.
arXiv Detail & Related papers (2025-02-06T04:16:20Z) - KVSharer: Efficient Inference via Layer-Wise Dissimilar KV Cache Sharing [58.29726147780976]
We propose a plug-and-play method called textit KVSharer, which shares the KV cache between layers to achieve layer-wise compression.
Experiments show that textit KVSharer can reduce KV cache computation by 30%, thereby lowering memory consumption.
We verify that textit KVSharer is compatible with existing intra-layer KV cache compression methods, and combining both can further save memory.
arXiv Detail & Related papers (2024-10-24T08:06:41Z) - Get More with LESS: Synthesizing Recurrence with KV Cache Compression for Efficient LLM Inference [78.65321721142624]
We focus on a memory bottleneck imposed by the key-value ( KV) cache.
Existing KV cache methods approach this problem by pruning or evicting large swaths of relatively less important KV pairs.
We propose LESS, a simple integration of a constant sized cache with eviction-based cache methods.
arXiv Detail & Related papers (2024-02-14T18:54:56Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.