Technique for Cache Management in Solid

Abstract

This research presents a novel cache management method for solid-state discs (SSDs) that aims to efficiently utilize the limited cache space and improve the cache hit rate. The method involves the establishment of various data structures, including a page cache, a replace block module, a new page linked list, a physical block chain list, and a physical page state list. When an input/output (IO) request from a host is received, it is processed through the page cache. In cases where a writing request is executed and the page cache is full, a block replace process is triggered within the SSD to free up space. To minimize erasure and page copy operations, the method selects a candidate replace block with the highest failure ratio from the rear half of the physical block chain list as a replacement. This ensures that a block written in the flash medium contains a maximum number of dirty data pages and a minimum number of effective data pages. The proposed cache management method is designed to enhance the overall performance of SSDs by reducing sequential rubbish recovery caused by the presence of dirty data pages, and it is also user-friendly and easy to operate.