Patent ID: 11940969
Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 9:
10. A computer program product comprising one or more computer readable storage media, and program instructions collectively stored on the one or more computer readable storage media, the program instructions comprising instructions executable by at least one processor for:
accessing a primary metadata tree providing a lookup path using a virtual address to locate data for a primary object in physical storage pointed to by a leaf node of the primary metadata tree;
providing a sub-tree from a leaf node of the primary metadata tree associated with the primary object, wherein the sub-tree provides derived object identifiers for objects derived from the primary object, with a copy leaf node of the sub-tree a sub-tree from the primary data's leaf node of the primary metadata tree, wherein the sub-tree provides lookup paths using virtual addresses for derived objects using copy nodes to represent derived object identifiers for objects derived from the primary object, and copy leaf nodes to point to physical storage locations of the derived objects, wherein a derived object is a view of the primary object at a specific point in time, and wherein the sub-tree is provided to reduce a number of copies of the primary object stored on the physical storage; and
maintaining an ancestry graph associated with the sub-tree with the ancestry graph linking derived object identifiers to provide an ancestral chain lookup to identify derived object identifiers of closest stored physical data of an associated derived object.