Benchmarking the application's performance by using CICS Performance Analyzer

Use CICS® Performance Analyzer (CICS PA) to analyze the performance of the application in a workload before you make any changes to the resource definitions, so that you can validate the performance improvement after redefining the resources. CICS PA can report on the time each transaction in the application spends on open TCBs and on the QR TCB, the time it spends in TCB switching, and the response time and dispatch time for the transactions.

Before you begin

  • These steps assume that you have already purchased, installed, and configured a CICS PA host for use with your CICS regions, and defined one or more relevant report sets. For instructions to do this, see CICS Performance Analyzer for z/OS.
  • These steps summarize a process for assessing the performance of an application. If you are not familiar with measuring and monitoring performance in CICS, read Measuring, tuning, and monitoring: the basics.

About this task

These instructions use the CICS PA interface that is available through TSO. You can also perform this task by using the CICS PA plug-in for CICS Explorer® to analyze the performance data.

If you do not have CICS Performance Analyzer available for your CICS regions, you can use other performance reporting tools such as IBM Z® Decision Support to analyze the SMF performance data. You could also use the CICS-supplied sample program DFH$MOLS to read, format, and print monitoring data. For information about alternative methods of processing monitoring data, see Processing CICS monitoring facility output.

Procedure

  1. Collect SMF performance data for a suitable workload involving the application.
    To collect performance data for the whole application, each CICS region that is used by the application must have the monitoring facility switched on. For instructions to turn on the monitoring facility in a running CICS region, see Controlling CICS monitoring.
    Tip: To assess the effect of your changes on the throughput of the application in your CICS systems, you need to collect performance data for a known workload, either by running a specific number of transactions, or by collecting performance data for a specific period of time.
  2. In TSO, start CICS Performance Analyzer using the method that you chose when you installed the tool on your systems.
    The Primary Option Menu is displayed.
  3. From the Primary Option Menu, select option 1, Personal Systems, and press Enter to display the Personal System Definitions panel.
  4. Select option 1, Define Systems, SMF Files and Groups, and press Enter to display a list of the CICS regions that are defined to the CICS PA host.
    Verify that the CICS regions used by the application are shown.
    If you need to add some of the CICS regions where the application runs, follow these steps:
    1. Press F3 to return to the Personal System Definitions panel. Select option 4, Take-up from SMF File, and press Enter.
    2. Specify the SMF file that lists the performance data for the application, and press Enter.
      CICS PA extracts the details of the CICS regions from the SMF performance data.
    3. Press F3 to exit to the Primary Option Menu. Select option 1, Personal Systems, and press Enter.
      CICS Performance Analyzer now displays the Data Take-Up from SMF panel. Press Enter to add the CICS regions that were extracted from the SMF data.
    4. In the Personal System Definitions panel, select option 1 and press Enter to view the list of the CICS regions that are defined to the CICS Performance Analyzer host.
      Verify that the CICS regions used by the application are now shown.
  5. Press F3 to exit to the Primary Option Menu. Select option 2, Report Sets, and press Enter.
  6. Select an appropriate report set to report on the application’s performance by entering S next to the report set and pressing Enter.
    If you do not have a suitable report set, type new on the command line and press Enter to define a new report set. For instructions to define a report set, see CICS Performance Analyzer for z/OS.
    Tip: For analyzing wait times, you can select multiple CICS regions for the report. Type S by Wait Analysis in the report set listing and press Enter to edit the selection of CICS regions.
  7. Enter run on the command line to run all the active reports defined in your selected report set. Confirm the run options and press Enter to run the report set.
    You can view the reports in the location that you defined for the job output for your report set.
  8. From your CICS Performance Analyzer reports, note the following performance measurements as benchmarks:
    • In the Wait Analysis reports for the application, CICS Performance Analyzer reports for each transaction the wait times and count for changing TCB modes. This information shows the time the application is currently spending in TCB switching.
    • In the Performance Summary reports for the application, CICS Performance Analyzer reports the average time that the transaction was running on each type of TCB.
    • In the Performance Summary reports for the application, CICS Performance Analyzer reports the average response time and dispatch (or processor) time for each transaction.
    • If you collected performance data for a known workload, note the number of instances of the application and the time taken to run them.