Machine Learning-Based Cache Replacement Policies: A Survey

Despite extensive developments in improving cache hit rates, designing an optimal cache replacement policy that mimics Belady’s algorithm still remains a challenging task. Existing standard static replacement policies does not adapt to the dynamic nature of memory access patterns, and the diversity of computer programs only exacerbates the problem. Several factors affect the design of a replacement policy such as hardware upgrades, memory overheads, memory access patterns, model latency, etc. The amalgamation of a fundamental concept like cache replacement with advanced machine learning algorithms provides surprising results and drives the development towards cost-effective solutions. In this paper, we review some of the machine-learning based cache replacement policies that outperformed the static heuristics.

An efficient Intelligent Cache Replacement Policy Suitable for PACS

An efficient intelligent cache replacement policy suitable for picture archiving and communication systems (PACS) was proposed in this work. By combining the Support vector machine (SVM) with the classic least recently used (LRU) cache replacement policy, we have created a new intelligent cache replacement policy called SVM-LRU. The SVM-LRU policy is unlike conventional cache replacement policies, which are solely dependent on the intrinsic properties of the cached items. Our PACS-oriented SVM-LRU algorithm identifies the variables that affect file access probabilities by mining medical data. The SVM algorithm is then used to model the future access probabilities of the cached items, thus improving cache performance. Finally, a simulation experiment was performed using the trace-driven simulation method. It was shown that the SVM-LRU cache algorithm significantly improves PACS cache performance when compared to conventional cache replacement policies like LRU, LFU, SIZE and GDS.