DBRC external trace

If you start the Generalized Trace Facility (GTF) and issue the CHANGE.RECON TRACEON command, the DBRC trace (DSPTRACE) creates an external trace record and issues the GTRACE macro to invoke GTF.

DBRC external trace records

The GTRACE macro passes the address and length of a DBRC external trace record to GTF. A DBRC external trace record is put in the user data area of a GTF trace record.

If more than two DBRC jobs run concurrently, the GTF data set or buffer can contain multiple trace records. Therefore, DBRC external trace records contain either the IMS subsystem ID or a job name. In a DB/DC or DBCTL environment, the SSID is added to the trace record. In other IMS environments, a job name is added to the trace record. The following table shows the format of these records.

Graphic shows GTF Trace Record format as GTF Prefix, then User Data. DBRC External Trace Record format has GTF Prefix, then SSID/Job Name, then User Data. DBRC Internal Trace Record has User Data.

The GTF cataloged procedure is supplied in SYS1.PROCLIB with member name GTF or GRFSNP. If you want the DBRC trace records to be put in the GTF data set, specify MODE=EXT on the EXEC parameter and USR on the GTF option in the cataloged procedure. For detailed information about invoking GTF and its cataloged procedure, see z/OS® MVS Diagnosis: Tools and Service Aids.

You can format and print DBRC trace records in the GTF data set by using the GTFTRACE subcommand of IPCS. You must specify the exit AMDUSRF2 on this subcommand. For detailed information about using IPCS, see z/OS MVS Interactive Problem Control System (IPCS) User's Guide.