IBM OS manual Scanner component, Detector component

The Scanner component

The Scanner is a batch utility that scans a load module library to detect those programs in the library that issue EXEC CICS commands that may cause transaction affinity. It examines the individual object programs looking for patterns matching the argument zero 3 format for the commands in question.

The Scanner detects the use of the EXEC CICS commands listed in Table 1 on page 11, and MVS POST requests.

The report produced by the Scanner indicates only that potential affinity problems may exist because it only identi®es the programs that issue the commands. It cannot obtain dynamic information about the transactions using the programs, or the names of the resources acted upon. Use the report in conjunction with the main report produced by the Reporter (see ªThe Reporter componentº on page 18).

Notes:

1.The Scanner operation is independent of the language the scanned program was written in and the release of CICS the scanned program was translated under.

2.The Scanner may indicate an affinity problem that does not really exist, because the bit pattern found accidentally matches the argument zero format for an affinity command.

3.The Scanner does not detect CICS macro-level commands.

	4. The Scanner distinguishes between ENQ by name and ENQ by address based
	on the presence of a length parameter on the EXEC CICS ENQ command. It
	does the same for DEQs. The reports show which ENQs and DEQs are by
	name and which are by address.
The Detector component

You can use the Detector in real-time to detect transaction affinities in a running CICS region, and to save details of the affinities in an MVS data space. This data is subsequently saved to DASD. The Detector consists of:

vA control transaction, CAFF

vAn autosave transaction, CAFB

vSome global user exit programs

vA task-related user exit program

This is shown in Figure 3 on page 13.

The data is collected by the global user exit programs at exit points XEIOUT,

XBADEACT, XMEOUT, and XICEXP, and a task-related user exit at task start and task end. Between them, these exit programs intercept all the EXEC CICS commands and other events (pseudoconversation end, terminal log off, user sign off) that are needed to deduce the affinities and their relations and lifetimes. These exit programs coexist with any other exit programs at the same exit points. (They can be placed before or after other exit programs, without any of the exit programs being affected.)

3. For an explanation of argument zero, see ªNotes on terminologyº on page x.

12 CICS Transaction Affinities Utility Guide