Open/Close Management window

The Open/Close Management window displays statistics on data set activity and drain requests. Use the Open/Close Management window to determine the number of open data sets, the number of drain requests, the number of page sets available to drain, and the number of successful and failed drains.

To display this window, select Open/Close Management from the DB2® Statistics Detail panel.

Figure 1. Open/Close Management window

 DGOMSWOC             Open/Close Management

                                          INTERVAL 3:32.419
 Open data sets
   High water mark . . . . . . . . . . . . . . . . . . :    106
   Current . . . . . . . . . . . . . . . . . . . . . . :    105
   Not in use, not closed
     High water mark . . . . . . . . . . . . . . . . . :    106
     Current . . . . . . . . . . . . . . . . . . . . . :    103
   In use  . . . . . . . . . . . . . . . . . . . . . . :      2

 Data sets closed - threshold reached  . . . . . . . . :      0

 Data sets converted from R/W to R/O   . . . . . . . . :   1295

 Command ===> _________________________________________________
  F1=Help         F2=Split        F3=Exit         F5=Auto
  F6=History      F9=Swap        F10=Delta       F11=Interval
 F12=Cancel      F16=Look        F17=Collect

The following list describes some of the important fields that are shown in this panel:

Open data sets - High water mark: The maximum number of data sets open concurrently (high water mark).
Monitor this field to see whether you are reaching the maximum number of open data sets permissible for your system. The maximum number of open data sets depends on the MVS version, modifications to your system, and various other factors. See z/OS® information in the IBM® Knowledge Center for the maximum number of open data sets permissible for your system.