This section covers:
CICS® statistics are the simplest and the most important tool for permanently monitoring a CICS system. They collect information on the CICS system as a whole, without regard to tasks.
The CICS statistics domain writes five types of statistics to SMF data sets: interval, end-of-day, requested, requested reset, and unsolicited statistics.
Each of these sets of data is described and a more general description of CICS statistics is given in Using CICS statistics and Appendix A. CICS statistics tables.
The CICS monitoring facility collects information about CICS tasks, and is described more completely in The CICS monitoring facility.
the CICS Customization Guide contains programming information on the data set formats, and the CICS Operations and Utilities Guide describes the monitoring utility programs, DFHMNDUP and DFH$MOLS.
The sample statistics program, DFH0STAT, produces a report showing comprehensive system information about a CICS system, its resources (except for terminals and FEPI resources), and an overview of the MVS™ storage in use. The program also demonstrates the use of the EXEC CICS INQUIRE and EXEC CICS COLLECT STATISTICS commands to produce an analysis of a CICS system. You can use the sample program as provided or modify it to suit your needs. Appendix E. The sample statistics program, DFH0STAT has more information about the DFH0STAT program, and lists the reports that it produces.
For the more complex problems that involve system interactions, you can use the CICS trace to record the progress of CICS transactions through the CICS management modules. Whereas a dump gives a "snapshot" of conditions at a particular moment, CICS trace provides a history of events leading up to a specific situation. CICS includes facilities for selective activation or deactivation of some groups of traces.
The CICS trace facilities can also be useful for analyzing performance problems such as excessive waiting on events in the system, or constraints resulting from inefficient system setup or application program design.
Several types of tracing are provided by CICS, and are described in the CICS Problem Determination Guide. Trace is controlled by:
Three destinations are available for trace data:
The measurement tools previously described do not provide all the data necessary for a complete evaluation of current system performance. They do not provide information on how and under what conditions each resource is being used, nor do they provide information about the existing system configuration while the data is being collected. It is therefore extremely important to use as many techniques as possible to get information about the system. Additional sources of information include the following:
This data, used with the data produced by the measurement tools, provides the basic information that you should have for evaluating your system’s performance.