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arXiv · 2510.08803

Man-Made Heuristics Are Dead. Long Live Code Generators!

Rohit Dwivedula·Divyanshu Saxena·Aditya Akella·Swarat Chaudhuri·Daehyeok Kim
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Abstract

Policy design for various systems controllers has conventionally been a manual process, with domain experts carefully tailoring heuristics for the specific instance in which the policy will be deployed. In this paper, we re-imagine policy design via a novel automated search technique fueled by recent advances in generative models, specifically Large Language Model (LLM)-driven code generation. We outline the design and implementation of PolicySmith, a framework that applies LLMs to synthesize instance-optimal heuristics. We apply PolicySmith to two long-standing systems policies - web caching and congestion control, highlighting the opportunities unraveled by this LLM-driven heuristic search. For caching, PolicySmith discovers heuristics that outperform established baselines on standard open-source traces. For congestion control, we show that PolicySmith can generate safe policies that integrate directly into the Linux kernel.

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Rohit Dwivedula, Divyanshu Saxena, Aditya Akella, Swarat Chaudhuri, Daehyeok Kim. 2025-10-09. Man-Made Heuristics Are Dead. Long Live Code Generators!. https://arxiv.org/abs/2510.08803

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