Data processing method to create virtual disks from non-contiguous

Abstract

A data processing method for storing groups of related information in a storage subsystem of a data processing system in which the storage subsystem includes one or more storage devices having a plurality of block addressable storage locations (blocks or sectors) each of which stores a predetermined fixed number of bytes of said information. The method includes the step of establishing allocatable increments of storage, called physical partitions, which comprise a predetermined number of contiguous addressable blocks, and initially allocating, in response to a request to the operating system, a preselected number of partitions for each group of related information, where the partitions in each group are not necessarily physically contiguous and where the number that is selected is the minimum number of partitions required to store the group of related information. The method further includes the step of automatically allocating one or more additional partitions, located physically on any device, to a previously allocated group of related partitions, dynamically in response to another request of the operating system. A group of partitions that have been allocated to store a group of related information, such as individual files that are related in a hierarchical file system, is called a 'Logical Volume'. Logical Volumes may be further combined for administration and data management reasons into a 'Volume Group'.