The net disk architecture for dynamic load balancing among disk arrays

A disk array is a proposed approach for a high-performance I/O subsystem. It requires dynamic load balancing against varying accesses to prevent some disks from becoming bottlenecks. Thus, we connected the disks by a bus and developed a local migration strategy to migrate data items with a high access frequency within the disk array. However, the bus may become a bottleneck when too many disks are connected to it. To solve this problem, we propose a net disk architecture, which contains multiple disk arrays connected by a crossbar network. Based on the load balancing within each disk array, a global migration strategy is developed to maintain the load balancing among the disk arrays. Therefore, load balancing is established for the entire architecture. Compared to conventional data reallocation techniques that are performed as a background process, dynamic load balancing is effectively maintained even though the disk arrays are burdened with a heavy load by the proposed architecture