Introduction.
Because CICS transactions can execute so quickly, looking at Task History may be the only way to evaluate the performance of a transaction. Often when looking at CICS Task History, it is apparent the transaction spent the bulk of its time in Db2. Or, from Db2 Thread History, you can see a task originated in a CICS Region. In both cases, it can be difficult to determine the exact instance of the thread in Db2 or the Task in CICS.
With IBM Z OMEGAMON for CICS V5.6.0 and IBM OMEGAMON for Db2 PE on z/OS v5.5.0, you can now simply correlate between the detailed history collected by the two products. Allowing the CICS user to quickly identify the thread in question and see all the attributes collected for it. The Db2 user can now rapidly determine details of the CICS task and, using the related tab, identify other CICS tasks which make up that unit-of-work.
Getting the Db2 information from CICS Task History.
First select the CICS Plex from the All Active CICSplexes workspace.
Use the ‘O’ Select for CICSplex Task History
The use the ‘I’ Select for Task History I/O
The has information directly from OMEGAMON for Db2. The fields that have highlighted titles are Zoom Linkage fields. Clicking on one of these fields will navigate directly to the OMEGAMON for Db2 Thread History for this CICS Transaction.
Clicking on “Plan Name”, “Elapsed Time” or “In-Db2 Elapsed time” links to the Db2 Accounting tab (“Acct”) in the Db2 Thread History Detail Accounting workspace.
Clicking on “Total Class 3 wait time” or “Total Class 3 events” links to the Db2 Class 3 Wait Time tab (“Class 3”) in the Db2 Thread History Detail Accounting workspace
Getting CICS Information from the Db2 Thread History.
From the All Active Db2 Subsystems workspace, Select ‘R’ for Thread History.
Enter the Thread History Filters.
Select a CICS Thread
The Subpanel titled CICS Task History Detail displays information from OMEGAMON for CICS Task History.
The highlighted are Zoom linkage fields.
Clicking on “Transaction ID” links to OMEGAMON CICS Task History Detail.
Clicking on “CICS Region Name” displays a pop-up with several possible actions that can be taken for that CICS Region.
CICS Region zoom.
Requirements.
IBM Z OMEGAMON for CICS and IBM OMEGAMON for Db2 PE must be installed and configured. Both must be configured to monitor the same Db2 subsystems.
IBM Z OMEGAMON for CICS PTF UJ09225 and IBM OMEGAMON for Db2 PE PTF UI83049must be applied.
Configuration.
In the CICS DB2CONN or DB2ENTRY definitions ACCOUNTREC must be set to UOW or TASK to create the correct LUWIDs that are common to DB2 and CICS. See CICS Transaction Server for z/OS Db2 Guide for more information about how the CICS/Db2 connections are defined. This configuration creates a field in the DB2 IFCID that allows identification of the CICS Transaction that created the Db2 Thread. Without this option this feature will not be able to work properly.
Conclusion
Being able to link from OMEGAMON CICS Task History to the Db2 Thread History for a specific CICS transaction will provide more information to determine the source of CICS transaction performance problems.
By Paul Kenney and Mick Harris
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