PRESERVING PAST STATES OF FILE SYSTEM NODES

A selective tuple versioning is used on a files system for preserving past states of file system nodes by adding a bitmap to a row for a node within a file system table for preserving the past state of the node in a file system, receiving a request for updating the node along with a node identification (ID) and associated attributes of the node needing to be updated, generating a second time value indicating the time of the updating, and duplicating the row for the node into a new row in the file system table with an end time set equal to the second time value if the bit in the bitmap for the node is set.