System for allocating storage spaces based upon required and optional service attributes having assigned priorities

A computer file system, for use with a computer system having a multiplicity of distinct data storage devices, includes a management program that defines a set of service attributes which characterize operational characteristics of data storage devices. A service class table stores data denoting which of service attributes characterize each distinct storage device. The management program adds data to the service class table when additional data storage devices are added to the computer system. A storage device selection program responds to file allocation requests, which specify a set of service attributes, by comparing the specified set of service attributes with the data stored in the service class table and selecting one of the data storage devices in accordance with predefined service attribute matching criteria. The service attributes used by the file system may include required service attributes and optional service attributes. In that case, the predefined service attribute matching criteria include criteria requiring that the required service attributes of the selected data storage device, as denoted in the service class table, match all required service attributes specified in the corresponding file allocation request. In addition, there are predefined criteria for maximizing matching of specified optional service attributes with the optional service attributes of the selected data storage device.