JVM program statistics

JVM program statistics are collected for every installed JVM program in the CICS region that runs in a JVM server. Statistics for programs that run in a JVM are collected separately from statistics for other programs, because the Java programs are not loaded by CICS®.

For public JVM programs, these statistics are mapped by the DFHPGRDS DSECT. For private JVM programs for applications that are deployed on platforms, these statistics are mapped by the DFHPGPDS DSECT. The statistics records for private JVM programs have information about the application for which the JVM program was defined.

JVM programs that are defined as application entry points are identified by a field in the statistics record. When interval statistics, end-of-day statistics, requested statistics, requested reset statistics, or unsolicited statistics are produced for a JVM program that is defined as an application entry point, two statistics records are written, one mapped by the DFHPGRDS DSECT for public JVM programs, and one mapped by the DFHPGPDS DSECT for private JVM programs.

Viewing statistics for Java programs

CICS does not collect statistics for Java programs when an EXEC CICS EXTRACT STATISTICS PROGRAM command is issued. To see them, you must use the EXEC CICS EXTRACT STATISTICS JVMPROGRAM command instead. However, when you browse program names by using the EXEC CICS INQUIRE PROGRAM command, Java programs are found. An application that collects statistics for programs by browsing with the EXEC CICS INQUIRE PROGRAM command, and then issuing the EXEC CICS EXTRACT STATISTICS PROGRAM command for the program names that it finds, would receive a “not found” response when it attempted to collect statistics for any Java programs.

To avoid receiving this response, make the application check the RUNTIME value for each program name that it finds. If the RUNTIME value is JVM, the application must not issue the EXEC CICS EXTRACT STATISTICS PROGRAM command for that program name. If you want to see the statistics for programs with a RUNTIME value of JVM, you can make the application issue the EXEC CICS EXTRACT STATISTICS JVMPROGRAM command for those programs. The statistics information that is collected for Java programs is not the same as the statistics information collected for other programs.

Java™ programs that run in a JVM have their own DFH0STAT report, the JVM Programs report. The DFH0STAT report for Program Totals also includes a figure for the number of Java programs, but this figure is obtained using the JVMPROGRAM keyword.