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arXiv · 1912.09770

CacheQuery: Learning Replacement Policies from Hardware Caches

Pepe Vila·Pierre Ganty·Marco Guarnieri·Boris Köpf
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Abstract

We show how to infer deterministic cache replacement policies using off-the-shelf automata learning and program synthesis techniques. For this, we construct and chain two abstractions that expose the cache replacement policy of any set in the cache hierarchy as a membership oracle to the learning algorithm, based on timing measurements on a silicon CPU. Our experiments demonstrate an advantage in scope and scalability over prior art and uncover 2 previously undocumented cache replacement policies.

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Pepe Vila, Pierre Ganty, Marco Guarnieri, Boris Köpf. 2019-12-20. CacheQuery: Learning Replacement Policies from Hardware Caches. https://arxiv.org/abs/1912.09770

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