PERFORMANCE ANALYSIS OF HYBRID DISK ARRAY ARCHITECTURES TO MEET I O REQUIREMENTS/

Disk array is an I/O subsystem incorporating multiple disks to improve the I/O performance, This paper considers general architectural model s of hybrid disk array systems which integrate asynchronous and synchr onous architectures together, An I/O workload is generally characteriz ed by average request size, average request rate, and mean response ti me requirement. In this paper, we propose an analytic performance mode l of hybrid disk array systems for a given I/O workload, With the help of the analytic model, we can determine the three important design pa rameters of a hybrid disk array system in order to meet the mean I/O r esponse time requirement. These parameters include the minimum number of required disks, the degree of declustering, and the degree of synch ronization. Our analytic model is verified by the simulation.