A plurality of storage devices of a plurality of types is provided. A plurality of criteria is associated for each of the plurality of storage devices, based on characteristics of the plurality of storage devices, wherein the plurality of criteria can be used to determine whether a selected storage device is a compatibility spare for a storage device in a storage device array, and whether the selected storage device is an availability spare for the storage device in the storage device array. A determination is made by a spare management application, based on at least the plurality of criteria and at least one optimality condition, of a first set of storage devices selected from the plurality of storage devices to be allocated to a plurality of storage device arrays, and of a second set of storage devices selected from the plurality of storage devices to be allocated as spares for the plurality of storage device arrays. An allocation is made of the first set of storage devices to the plurality of storage device arrays. An allocation made of the second set of storage devices as spares for the plurality of storage device array.