Directory update method and directory updates, as well as, tree structure type data storage device

摘要

PPROBLEM TO BE SOLVED: To provide a distributed directory storage device efficiently updating a tree structure in data update on a Fat-B tree structure. PSOLUTION: The distributed directory storage device 1 is provided with a first phase execution means 631 searching for the lowermost node with the entry number below a previously determined limit and a second phase execution means 632 setting an exclusive latch to a node below the searched node, update a leaf node 31 when an exclusive latch is set to a parent node serving as a division object according to update of the leaf node 31, and expanding the range of the exclusive latch when no exclusive latch is set in the parent node to be divided. PCOPYRIGHT: (C)2006,JPO&NCIPI