Unit 9, Section 5: Unidirectional Direct Logical Parent Pointer, Part 2

With direct pointers, the number of I/Os and CPU time required to access any individual logical parent is usually minimized. DL/I can directly access the exact location in the CI/block that contains the target LP segment without first accessing any parent segments (up to the root) or the index database if HIDAM or to follow any PCF and PTF pointers if the LP segment is not a root.