延迟命中缓存的下限
Lower Bounds for Caching with Delayed Hits
摘要：
高速缓存是对延迟敏感的计算机系统的基本组件。[ASWB20]最近的工作已经开始了对延迟命中的研究：当缓存和后备存储之间的延迟远远大于新请求之间的时间时，缓存中会出现这种现象。我们给出了延迟命中缓存模型的两个结果。(1)竞争比下限。我们证明了[ASWB 20]中算法的竞争比，以及更一般地任何延迟命中的确定性在线算法的竞争比，至少是Omega（kZ），其中k是缓存大小，Z是延迟参数。(2)延迟命中潜伏期的反单调性。反单调性是缓存延迟的自然期望属性：具有缓存命中而不是缓存未命中应该导致较低的总体延迟。我们证明了延迟命中模型的延迟是不反单调的表现出的情况下，有一个缓存命中，而不是一个未命中的结果在整体延迟的增加。我们还提出了一个修改的延迟命中模型，使延迟反单调。
英文摘要：
Caches are a fundamental component of latency-sensitive computer systems. Recent work of [ASWB20] has initiated the study of delayed hits: a phenomenon in caches that occurs when the latency between the cache and backing store is much larger than the time between new requests. We present two results for the delayed hits caching model. (1) Competitive ratio lower bound. We prove that the competitive ratio of the algorithm in [ASWB20], and more generally of any deterministic online algorithm for delayed hits, is at least Omega(kZ), where k is the cache size and Z is the delay parameter. (2) Antimonotonicity of the delayed hits latency. Antimonotonicity is a naturally desirable property of cache latency: having a cache hit instead of a cache miss should result in lower overall latency. We prove that the latency of the delayed hits model is not antimonotone by exhibiting a scenario where having a cache hit instead of a miss results in an increase in overall latency. We additionally present a modification of the delayed hits model that makes the latency antimonotone.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
