Method, apparatus, and computer program product for using an array of high performance storage drives included in a storage array to reduce accessing of an array of lower performance storage drives included in the storage array

A method, apparatus, and computer program product are disclosed for controlling accesses of drives in a storage subsystem. A first array of a first type of drive is provided. The first type of drive is a server class of drive. A second array of a second type of drive is provided. The second type of drive is a PC class drive. The first and second arrays are bound together to form a single array of drives. The single array of drives is presented to a host that is coupled to the storage subsystem as a single array. The host is unaware that the single array includes two different types of drives. Data is stored in the second array of drives. Data is migrated from the second array of drives to the first array of drives when an access rate of the second array of drives exceeds a threshold access rate for the second type of drive.