Patent ID: 8862923

Claim:
A method for managing a power state of a set of data storage devices (device set) coupled to and controlled by a storage subsystem using a file system, wherein the file system receives read and write requests and passes them to the storage subsystem, the method comprising: determining an idleness measure at the file system, the idleness measure indicating availability requirements of data corresponding to the device set; setting an idle state based on the idleness measure; receiving the idle state setting at the storage subsystem; determining at the storage subsystem the device set based on the data that the idleness measure determined by the file system indicates the availability requirements of; determining whether the idle state setting is different from a current idle state of the device set; determining whether to change the current idle state of the device set if the idle state setting is different from the current idle state of the device set, the determining being based on information about the device set; and commanding the device set to change the current idle state to correspond to the idle state setting based on determining whether to change the current idle state.