Identifying Critical Activities
After you have determined that the measurement data collected by Strobe contains the information you want to examine, you need to identify which activities occur most often when the CICS application runs. You know that the performance of the transactions CDUN, CSRV, and BACK is not meeting your expectations. Check on their performance first in the Transaction Summary report to determine how much extra CPU time the transactions are consuming.
Transaction Summary Report
Depending on the type of reporting parameters you set as described in the section Measuring a CICS Region, your Performance Profile will contain different types of data in the Transaction Summary report . This report example, produced without Transaction Profile data collection, shows the transactions that Strobe found executing during the measurement session. Transactions CDUN and CSRV accounted for far more activity than the other reported transactions. Together, their execution constituted a high percentage of the CPU time used within the CICS region. The CICS Transaction Profile reports described in DFHFCP: The CICS File Control Program allow you to see more detail about what is causing the CPU consumption by CDUN and CSRV.
This report also confirms that response times for transaction BACK are erratic and, at times, too long. The median service time for BACK is under two seconds, but 85% of the time service time averages more than 13 seconds.
Transaction Summary Report
Time Distribution of Activity Level Report
The Time Distribution of Activity Level Performance Supplement report (See the following figure) shows that the datasets ORDERFL and CUSTOMER are sporadically under heavy demand. You know that the problem transaction BACK frequently uses ORDERFL and that CDUN and CSRV use CUSTOMER. Both of these file access activities deserve attention. BACK also accesses the PRODUCT dataset, where usage appears low, but is actually high in relation to the number of BACK transactions processed. Interpreting-Strobe-CICS-transaction-profile contains examples of the CICS Transaction Profile reports that show how much time the CDUN, CSRV, and BACK transactions actually spend accessing the ORDERFL and CUSTOMER datasets.
Time Distribution of Activity Level Report
