Implementing an XEIIN global user exit
The XEIIN global user exit can be useful if an overlay is not being detected until CICS® task termination is doing the final freeing of storage. CICS® can detect a Storage Accounting Area (SAA) overlay either during an explicit FREEMAIN or during task termination. If detected at task termination, the task is not abended by CICS® and hence Fault Analyzer is not invoked. CICS® attempts to take a system dump, with dump code SM0102, however if CICS® system dumps are being suppressed, further analysis is not possible.
To assist with SAA overlays Fault Analyzer provides a program that can optionally be installed in the XEIIN global user exit. If installed, this program, at each EXEC CICS® RETURN statement, validates all the CICS® storage accounting areas for the current task. If an overlay is found, then one of two actions can be performed:
- A call can be made to take a CICS® transaction dump with
dumpcode IDIS.
If Fault Analyzer is installed in the XDUREQ global user exit, then this transaction dump is analyzed in the normal manner with a history file fault entry being created.
- An SDUMP of the CICS® region can be taken.
The request to take this SDUMP is made by the IDIS subsystem, and as such, it is not affected by the CICS® system dump suppression setting. If a SDUMP is captured, then it can then be analyzed interactively by way of the File menu option 5.
Enabling the Fault Analyzer XEIIN global user exit program, and setting which action should be performed, is done using the Fault Analyzer supplied CFA transaction. Unlike the other Fault Analyzer CICS® exits, there is no option to enable the XEIIN exit during CICS® PLT processing.
When invoked, the initial CFA display is similar to the following:
Fault Analyzer Control Transaction
Options: I=Install U=Uninstall
Current Status/Error Message
_ XPCABND Installed
_ XDUREQ Installed
_ LE Exit Installed
_ SDUMP Screening Installed
_ XEIIN Uninstalled
Current HWM Setting MWS
Active 0000 0001 0001
Waiting 0000 0000 0017 0000
IDITRACE OFF DeferredReport ON
PF1=Help PF3=Exit PF4=Opts PF5=Clear FND Area PF9=IVP PF11=TRACE ENTER=Update
From this display, an "I" can be entered next to XEIIN to install the exit. A screen similar to the following is then displayed:
Fault Analyzer Control Transaction
Options: I=Install U=Uninstall
Current Status/Error Message
_ XPCABND Installed
_ XDUREQ Installed
_ LE Exit Installed
_ SDUMP Screening Installed
_ XEIIN Installed N TXN dump N SDUMP Set at least one option to Y
Current HWM Setting MWS
Active 0000 0001 0001
Waiting 0000 0000 0017 0000
IDITRACE OFF DeferredReport ON
PF1=Help PF3=Exit PF4=Opts PF5=Clear FND Area PF9=IVP PF11=TRACE ENTER=Update
In this screen, enter "Y" next to either TXN dump or SDUMP to
set the action to take when an SAA overlay is detected.
The I (Install) option must be used each time the TXN or SDUMP field is changed.