This paper presents a summary analysis of the Least Frequently Used (LFU) and Perfect Least Frequently Used (PLFU) cache eviction algorithms on real data, transferred on Content Delivery Nettworks (CDNs), as well as on Zipf distributed samples. In light of the growing emphasis on energy efficiency in CDNs in recent years due to rising energy costs, this paper considers and discusses the total CPU time required to run a cache algorithm. The total CPU time represents a novel metric for evaluating cache performance, and it is contrasted with the conventional Cache Hit Ratio (CHR) metric. Furthermore, a new algorithm with an admission policy and the eviction strategy that of PLFU is presented. The results demonstrate that it is a simple and straightforward algorithm to implement and offers high CHR and low CPU time.

翻译：本文针对实际内容分发网络（CDN）传输数据及Zipf分布样本，对最不经常使用（LFU）算法与理想最不经常使用（PLFU）缓存淘汰算法进行了综合分析。鉴于近年来能源成本上升导致CDN能效日益受到重视，本文重点考察并讨论了运行缓存算法所需的总CPU时间。总CPU时间作为评估缓存性能的新指标，与传统的缓存命中率（CHR）指标进行了对比分析。此外，本文提出了一种采用准入策略并沿用PLFU淘汰机制的新型算法。实验结果表明，该算法实现简洁直观，在保持高缓存命中率的同时显著降低了CPU时间消耗。