The Library Utility option S displays information (Figure 1) for data sets that reside on Storage Management Subsystem volumes (also called managed data sets) when:

• DFSMSdfp is installed and available
• Storage Management Subsystem is active.

The major difference between this information and the information that is displayed for data sets on non-managed volumes is the addition of these classes:

• Management class
• Storage class
• Data class

If the data set is a PDSE, the "Data set name type" field is LIBRARY. Because the used blocks and used extents are not applicable to a PDSE, the Data Set Information panel replaces these values with "Used pages" and "% Utilized" (Figure 2). Other values that can appear in the "Data set name type" field are:

• HFS - MVS™ Hierarchical File System data set
• EXTENDED - DFSMSdfp Striped data set. When the Data Set Name Type is EXTENDED, the SMS Compressible field indicates if the data set is compressible or not (YES or NO).
• LARGE - Large format sequential data set