A system, method, and computer readable medium that facilitate operation of a file system capable of dividing an existing homogeneous file system into a series of regions, with each region accommodating storage devices having compatible characteristics are provided. The file system is divided into logical regions, with each region containing a particular class of storage devices possessing a particular set of common storage traits. The regionalization of the file system provides for all cylinders of storage devices sharing a common storage characteristic to be contained within a single region, and dedicated file system logic can be written to service that region. A master index configuration implemented in accordance with disclosed embodiments includes a region descriptor construct that enables cylinder index descriptors associated with cylinders of storage devices sharing a common storage characteristic to be grouped into regions.