Systems and methods for hierarchical reference counting via sibling trees

摘要

Systems and methods for hierarchical reference counting via sibling trees are provided. The hierarchical data structure, together with its associated operations, can efficiently maintain reference counts and significantly reduce input/output (IO) operations compared to traditional techniques. The data structure presented here is applicable to any directed acyclic graph (DAG-type) structure where reference counts are used. Various embodiments of the present invention use a data structure to maintain a “sibling pointer” (pointing to the sibling node as a way to avoid reference count updates) and a “sibling count.” When nodes in the tree diverge, the sibling pointer and sibling count are updated as opposed to directly manipulating the reference counts of the children of the diverging nodes. Various other embodiments can use additional entries or fields that allow for improved efficiency and advantages.