Image Number 5 for United States Patent #7418531.
The invention classifies volumes (e.g., file systems or LUNs) of a data storage system according to application requirements and allocates space for the volumes on storage devices (e.g., hard disk drives) accordingly. A person such as an IT administrator configures the volumes specifying size, type (e.g., file system or SAN LUN), and priority (e.g., high, medium, low, or archive). The host schedules I/O requests to the storage devices in priority queues using the volume definition to match the application requirements and reduce storage seek time between volumes of different priorities. The host also allocates high performance bands of the storage devices to high performance applications and lower performance bands to lower performance applications. In this manner, the data storage system places data on the band of the storage device that best supports its performance needs.