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arxiv.org/abs/2402.residual-cachingSidenote

Residual Cache Reuse for Low-Latency Inference

Preprint · 22 pages · February 2026

We propose a residual caching scheme in which attention states from prior requests are reused when prompt prefixes match, reducing time-to-first-token substantially on chat workloads.

In evaluation across three serving stacks, median latency fell 41% while quality metrics were unchanged. The approach requires no model modification and no retraining.

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This paper introduces residual caching: attention states from earlier requests are reused when prompt prefixes match 1. Median latency dropped 41% with no quality regression 2, and the method needs no retraining 3.
PDF · arXivv2.10.0
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