Space Monitor Graph report

This report is a scatter plot that shows space allocation and use information.

Subsections:

Report example
Report field description
Interpreting the scatter plot data

Report example

The following figure shows an example of the Space Monitor Graph report.

Figure 1. SPMNPRT: Space Monitor Graph report

IMS HIGH PERFORMANCE POINTER CHECKER FOR z/OS - SPMN              "SPACE MONITOR GRAPH REPORT"                           PAGE:     1
5655-U09                                                   DATE: 08/31/2021  TIME: 18.39.52                         FABKSPMN - V3.R1 
 
                MEMBER: N/A                                IMS DATA SET
                DBORG: HDAM  /VSAM   DBNAME: DSCLSDVN    DDNAME: DSCLSDV0    DSNAME: TESTDB.SAMPLE1.SPMN.DSCLSDV0
   3390-3
(CYLINDERS)        LEGEND:    * = ALLOCATED SPACE    - = IMS DATA     + = USED SPACE (INCLUDING NON-REUSABLE IMS FREE SPACE)
   50 |
      |
      |
      |
      |
   45 |
      |
      |
      |
      |
   40 |
      |
      |
      |
      |
   35 |
      |
      |
      |
      |                                                                            *             *     31
   30 |
      |                                                                 *
      |
      |                                                    *      *
      |                                                                            +             +     26 ( 83.9%)
   25 |    *     *       *       *       *      *
      |                                                                 +
      |                                         +          +      +
      |
      |                                  +
   20 |
      |
      |                          +                                                 -             -     18 ( 58.1%)
      |
      |                  +                                              -
   15 |    +     +                                                -
      |                                         -          -
      |
      |                                  -
      |
   10 |    -     -       -       -
      |
      |
      |
      |
    5 |
      |
      |
      |
      |
    0 |
      |------+------+------+------+------+------+------+------+------+------+------+------+------+
           06/08  06/15  06/22  06/29  07/06  07/13  07/20  07/27  08/03  08/10  08/17  08/24  08/31

Report field description

This report contains the following information:

MEMBER

Name of the member specified by the EXEC PARM parameter. If no member name is specified by the EXEC PARM parameter (that is, control statements are specified in the FABKCTL or SPMNIN data set), N/A is shown.

DBORG

Database organization type. The format is:

     xxxxx/yyyy

Where:

xxxxx: HDAM, HIDAM, HISAM, SHISAM, PINDX (HIDAM index), SINDX (secondary index), PHDAM, PHIDAM, PHINDX (PHIDAM index).
yyyy: VSAM or OSAM

In the case of an OS data set, only 'VSAM' or 'NON-VSAM' is shown.

DBNAME

Database name. This field is left blank in the case of an OS data set.

DDNAME

DDname of the data set. This field is left blank in the case of an OS data set.

DSNAME

Data set name

Interpreting the scatter plot data

The scatter plot shows the following data for each data set:

Allocated space
Used space
IMS data (space used for IMS data)
IMS data is produced only for the IMS full-function database data sets that have entries in the HISTORY data set.

X-axis shows the date. A unit of scale corresponds to one day. The recent 90 days of space information is shown on the graph up to the date of this Space Monitor run.

Y-axis shows the amount of space in cylinders. The maximum and minimum scale values are determined by the maximum and minimum space values. If the maximum space value is more than 99999 cylinders, the maximum scale value is printed as 99999+. A device type is shown at the top of Y-axis. If an asterisk * is marked after device type, for example 3390-A*, it means Extended Address Volume (EAV).

The following is the description of the scatter plot data:

ALLOCATED SPACE

The space allocated for this data set is shown as the asterisk (*) marks.

IMS DATA

The space used as IMS data in this data set is shown as minus (-) marks. For an OS data set, this value is always shown as zero.

The space used as IMS data is as follows, depending on the database type:

For HDAM and HIDAM databases, it is the total space used by the IMS segments in the data set.
For index databases, the value is calculated as follows:
```
(Total number of segments in the data set) x (Logical record length)
```
Note: In the case of shared index databases, the space information is reported for one secondary index portion only.
For HISAM databases, the value is calculated as follows:
```
(Total number of segments in the data set) x (Average segment length)
```
Note: The average segment length is the average for the entire database, including both the primary data set and overflow data set.

USED SPACE

The space used for this data set is shown as plus (+) marks. For VSAM data sets, the space includes VSAM CI splits and CA splits.

For HDAM, HIDAM, PHDAM, and PHIDAM database data sets, USED SPACE is calculated as shown in the following figure and is illustrated in Figure 3.

Figure 2. Formula to calculate USED SPACE (HDAM, HIDAM, PHDAM, and PHIDAM)

   USED SPACE = ALLOCATED SPACE - usable free space

For index database data sets, HISAM database data sets, and OS data sets, USED SPACE is the high-used-RBA and is illustrated in Figure 3.

For a VSAM data set, USED SPACE is the high-used-RBA.

Notes:

On the report, where the asterisk (*) mark intersects other marks (+ or -), the asterisk mark overrides others. Where the plus (+) mark intersects the minus (-) mark, plus mark is shown.
If the space that is allocated or used for the data set is more than 99999 cylinders, the amount of the space is shown as 99999+.
If the space that is allocated for the data set is more than 99999 cylinders, the percentages of the used space as IMS data and the used space for the data set are shown as N/A%.

The following figure provides a brief overview of how a VSAM data set is used. When you analyze the Graph report, this figure helps you understand the fields that are printed in the report.

This figure provides a brief overview of how a VSAM data set is used. — Figure 3. Overview of how a VSAM data set is used: Graph report