Managing locality in space reuse in a shadow written B-tree via interior node free space list

摘要

A method for managing space re-use with respect to the indices (nodes) of shadow written tree organized dynamic random accessed files/records/pages located in the external store of a CPU. The method reserves space in all non-leaf nodes and maintains a list of available node addresses. When a new node is required then space, if available, is obtained from the parent node list. Only when the parent list becomes exhausted is space (node) obtained from a node inventory manager. Deletion of a node causes its address to be placed on the free or available list maintained by that node's parent. If there is no space, then space on the parent node list is obtained by returning to the inventory manager that node on the list having the least locality with the existing subordinate (children) nodes of the parent.