CICS IA interdependency functions
CICS® IA assists in understanding, in a controlled manner, the inter relationships between the shared common resources of applications and services.
Many large organizations have been using CICS since the early 1970s, their systems growing and evolving with the business. During this time, many techniques for implementing applications have been used, as a result of new function, changing corporate standards, technical requirements, and business pressures. Frequently, this growth has not been as structured as it might have been, with the result that many applications and services share common resources, and changes in one area typically affect many others. Unstructured growth can reach such a level that the system can no longer develop in a controlled manner without a full understanding of these inter relationships. CICS IA can help you achieve this understanding.
For example, to change the content or structure of a file, you must know which programs use this file, because they will need to be changed. CICS IA can identify the programs and the transactions that drive the programs.
CICS IA records the interdependencies between resources, such as files, programs, and transactions, by monitoring programming commands that operate on resources. The application that issues such a command has a dependency on the resource named in the command. For example, if an application program issues the command EXEC CICS WRITE FILE myfile it has a dependency on the file called “myfile”. It might have similar dependencies on transient data queues, temporary storage queues, transactions, and other programs.
- EXEC CPSM calls to CICSPlex® SM resources
- EXEC SQL calls to DB2® resources
- MQ calls to WebSphere® MQ resources
- EXEC DLI calls and language-dependent native calls to IMS™ Database resources
- Dynamic COBOL calls to other programs
All the CICS and non-CICS commands that can be monitored are listed in Details of dependencies and affinities collected.
The Collector component of CICS IA collects the dependencies that apply to a single CICS region; that is, a single application-owning region (AOR) or a single, combined routing region and AOR. It can be run against production CICS regions and is also useful in a test environment, to monitor possible dependencies introduced by new or changed application suites or packages. From the interactive interface of CICS IA, you can control Collectors running on multiple regions.
CICS IA collects these dependencies into a database. You can store the dependency information from several CICS regions into the same database.
You can review the collected dependencies using the CICS IA Query interface, or list them using the Reporter.
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