If you select option S, information about the selected data set
is displayed. The information displayed by option S is the same as
that displayed by option S of the Data Set utility (option 3.2), but
it differs from option I in two respects. Information for partitioned
data sets, when displayed by option S, lacks the number of maximum
and used directory blocks, and the number of members. For sequential
data sets, options I and S display the same information. You can not
enter a volume serial when you are requesting information on multivolume
data sets.
Note: - The space for data sets allocated in blocks is calculated as if
all of the tracks, including the last one, contain only full blocks
of data. Any partial "short" blocks are ignored.
- The information shown for current space utilization is the actual
data that the data set contains, based on the number of allocation
units (blocks, tracks, bytes, megabytes, and so on) that have been
written. For a data set allocated in units other than tracks and cylinders,
it does not include the unused portion of a track that is only partially
filled.
For example, if a data set allocated in bytes with block
size of 600 has one block written to a device with a track size of
1000, 600 bytes of data are written and the remaining 400 bytes cannot
be used by a different data set. A track is the smallest possible
unit of physical allocation to a data set on DASD. ISPF reports 600
bytes used while other products (such as ISMF) report 1000 bytes used.
ISPF reports the space occupied by data in the data set. ISMF reports
the space used by this data set that is not available for use by another
data set. The difference is a relative indication of the effectiveness
of the block size used when the data set was created.
Figure 1 shows a short format example of
data set information for a partitioned data set. This is the short
format ISPF uses to display data set information when DFSMSdfp is
not installed or not available, or when the Storage Management Subsystem
is not active. See Short information for managed data sets to see
how ISPF displays data set information when these products are installed,
available, and active.
Figure 1. Short data set information
(ISRUAIP) Data Set Information
More: +
Data Set Name . . . . : MYPROJ.DEV.SOURCE
General Data Current Allocation
Management class . . : STANDARD Allocated cylinders : 1
Storage class . . . : BASE Allocated extents . : 1
Volume serial . . . : MVS8WF
Device type . . . . : 3390
Data class . . . . . : **None** Current Utilization
Organization . . . : PO Used cylinders . . : 1
Record format . . . : FB Used extents . . . : 1
Record length . . . : 80
Block size . . . . : 27920
1st extent cylinders: 1
Secondary cylinders : 1
Data set name type : PDS
Creation date . . . : 2002/07/08 Referenced date . . : 2002/07/31
Expiration date . . : ***None***
Command ===>
F1=Help F2=Split F3=Exit F7=Backward F8=Forward F9=Swap
F12=Cancel
The "Allocated units" and "Used units" fields can vary,
depending on the value that was specified in the "Space units" field
when you allocated the data set. For example, Figure 1 shows
what the short format of the Data Set Information panel would look
like if the data set was allocated by specifying CYLS in the "Space
units" field.