The application of two-level cache in RAID system

In a RAID system, the cache is one of the important factors that can affect general system performance. As a two-level cache usually brings better performance than a one-level cache in the processors of personal computers and embedded systems, a two-level cache system that exploits both temporal and spatial localities effectively is proposed as the cache structure for a RAID system. The proposed cache system consists of two layers of caches, i.e., a set associative cache with small block size and a fully associative spatial cache with large block size. According to the results of simulation, the hit ratio and hit times can be improved with the two-level cache structure.