Controlling and customizing exception analysis

Although customizing exception analysis is generally part of the installation process, OMEGAMON® for IMS allows individual users to customize their sessions and save the settings in profiles for later recall.

You can customize exception analysis in the following ways:
  • Group definition
  • Exception group switches
  • Exception control
  • Invocation order

You can save the settings that you define in a user profile. New group settings are not saved in the user profile. To reuse those settings in future OMEGAMON for IMS sessions, save them in a screen space and invoke the screen space at the start of your session.

Defining group exceptions

You can define your own exception groups by using the GDFN command. You might want to supplement or change the default groupings to organize exceptions in groups that are related to your application. You can also group highly critical exceptions that have a potentially severe impact on the system.

Some advantages of defining exception groups are:
  • Related or critical exception messages appear when you invoke exception analysis by group. They are more visible because they are shown at the beginning of the display.
  • A summary of the last and worst occurrences of exception warnings by group displays on the History of all Tripped Exceptions panel.
  • You can set group switches by using the XGSW command to determine the invocation state of the exception group as a whole. To display the existing groups, enter XGSW.

See the IBM® OMEGAMON for IMS on z/OS®: Realtime Commands Reference for more information about the GDFN and XGSW commands.

Setting group switches

You can control the state of all exceptions within a specified group by using the XGSW command. For example, you can turn all exceptions in a group on or off at once, force a sample warning message for each exception in a group for testing purposes, or suppress the display of messages for a group even though the exception switch is on. The latter option is useful for the Exception Logging Facility (XLF) and Automatic Screen Facility (ASF).

The group switch overrides individual exception settings (unless you define a null state for the group).

You can list the existing groups or change them. To change the status of a group, add the keywords on the XGSW command.

The following example of XGSW specifies that the IM group of exceptions is on and can be logged, but does not display on the terminal.
XGSW GROUP=IM STATE=NDSP
See the IBM OMEGAMON for IMS on z/OS: Realtime Commands Reference for more information about the XGSW command.

Controlling individual exceptions

OMEGAMON for IMS provides a set of panels from which you can view the current characteristics of an exception or change the characteristics of an exception. On these panels, you can dynamically change the settings of each keyword in the display by typing over the displayed value and pressing Enter. You can access these panels from the Profile menu (option P on the Main menu). Any new definitions that you create can be saved in a user profile for future OMEGAMON for IMS sessions.

Some of the options on this panel focus attention on an exception message. For example, you can cause the terminal bell to ring, control the color in which a warning displays, and assign display attributes that highlight the message. The following figure shows an example of the Set Communications External Subsystem Pool Exceptions panel that shows the current characteristics for the ACEA exception (option P.A.A).
Figure 1. Set Communications External Subsystem Pool Exceptions panel
 ________________ KOIODFB  VTM     OI-II    V530./C I91C 03/25/15  9:42:00    B
> Help PF1       Back PF3        Up PF7        Down PF8       Save Profile PF22
===============================================================================
>            Set Communications External Subsystem Pool Exceptions
 
> To display the threshold of an exception, remove the > preceding XACB,
> and type the exception name following LIST=.
 
> To change the setting for an exception, type over the current setting
> and press ENTER. To make your changes permanent, you must SAVE your
> OMEGAMON profile.
 
>XACB LIST=cccc
 
> The CESS exceptions is:
 
>          ACEA  Utilization > n%.
===============================================================================
Use the panel to specify five types of parameters for each exception.
Display
Specifies display characteristics for the exception, such as the two-character group name that identifies the type of exception, whether the exception is ON or OFF, and whether to activate an audible alarm when the exception trips.
Box
Specifies whether you want the warnings for this exception to be enclosed in a box. If not, specify NOBOX. Otherwise, you can specify the characteristics for the box, including the box color, intensity, and attributes such as blinking, reverse video, and underlining.
Threshold
Sets the exception threshold, typically numeric. You can also set display color and attributes for the exception message if you do not request a boxed message.
Cycle
Limits OMEGAMON for IMS exception checking, which restricts the use of CPU time to test high overhead exceptions.

The EXNCYC keyword sets the frequency for checking exceptions. For example, you can choose to have OMEGAMON for IMS check for a particular exception condition only every 5 or 10 cycles. See the .NXE immediate command in the IBM OMEGAMON for IMS on z/OS: Realtime Commands Reference for information about controlling the frequency of display.

The STOP keyword stops the checking of exceptions after they trigger the specified number of times. It also displays how many times an exception triggered since STOP= was reset.

The CUMULATIVE keyword is informational, indicating how many times an exception triggered during the session.

XLF
For a description of the XLF parameters, see the exception logging facility in the IBM OMEGAMON for IMS on z/OS: Realtime Commands Reference.
The following keywords can be used with the XACB command shown in Figure 1.
LIST=
Allows you to list the exceptions to display or modify.
GROUP=
Allows you to limit the list of exceptions to those exceptions in the specified exception group.
FORCE
Displays the current value of the exception as a sample exception message.
TERSE
Displays an abbreviated, single-line status for each defined exception, showing the threshold value, display color, exception state, and the state of the bell.
The following example shows output from XACB commands that use the TERSE keyword.
Figure 2. TERSE keyword display
  ________________ KOIODFB  VTM     OI-II    V530./C I91C 03/25/15  9:43:18    B
 > Help PF1       Back PF3        Up PF7        Down PF8       Save Profile PF22
 ================================================================================
             Set Communications External Subsystem Pool Exceptions
 
 > To display the threshold of an exception, remove the > preceding XACB,
 > and type the exception name following LIST=.
 
 > To change the setting for an exception, type over the current setting
 > and press ENTER. To make your changes permanent, you must SAVE your
 > OMEGAMON profile.
 
  XACB LIST=ACEA TERSE
 : ACEA          Threshold=60       Display=DEFAULT   State=ON    Bell=OFF
 
  The CESS exceptions are:
 
 >          ACEA  Utilization > n%.
 ================================================================================

  XACB TERSE
 : DNRS Threshold=N/A  Display=Red   State=ON     Bell=ON
 : TNRS Threshold=N/A  Display=Blue  State=TEST   Bell=OFF
 : WSHI Threshold=2500 Display=Pink  State=ON     Bell=OFF
 : WSLO Threshold=300  Display=Blue  State=NDSP   Bell=OFF

Reordering the display

You can display a list of the exceptions and the order in which OMEGAMON for IMS executes and displays them by using the LEXC command. The following figure shows a partial display of the exceptions in the OMEGAMON for IMS default order:
Figure 3. Exception order displayed by the LEXC command
  ________________ KOIMENU  VTM     OI-II    V530./C I91C 03/25/15  9:44:43    B
 LEXC
:      INAC =  1   TCOI =  2   TCOT =  3   DISP =  4   DNRS =  5   TNRS =  6
:      DRDY =  7   TRDY =  8   IORC =  9   SPAH = 10   QBKH = 11   SMGH = 12
:      LMGH = 13   RDSH = 14   MFSH = 15   TMFH = 16   ACBH = 17   OSBL = 18
:      SAPW = 19   ITWH = 20   COMW = 21   SDSP = 22   CROL = 23   ARSP = 24
            .           .           .           .           .           .
            .           .           .           .           .           .
            .           .           .           .           .           .

To dynamically change the order of the exceptions, type over an exception name or its number. You can save the new definition in your user profile.