US Patent 7594085 Reclaiming data space

A first contiguous group of one or more storage locations to be virtually reclaimed is determined, where the first contiguous group is smaller than a minimum allocation group size and the storage locations are used to store previous version data. The first contiguous group is virtually reclaimed. A second contiguous group of one or more virtually reclaimed storage locations to be made available for reuse is determined, where the size of the second group is greater than or equal to the minimum allocation group size. The second contiguous group is made available for reuse.