Perform this step once for each z/OS image. You only need to perform this step if you want an external DASD record of trace data. IBM recommends that you keep a history of DFSMSrmm PDA trace data in case a problem is reported to IBM.

The problem determination aid (PDA) facility gathers DFSMSrmm processing information to enable analysis to pinpoint module flow and resource usage related to DFSMSrmm problems. The PDA facility is required for IBM service because it traces module and resource flow. The PDA facility consists of in-storage trace, optional DASD log data sets, EDGRMMxx parmlib member options, and operator commands to control tracing.

DFSMSrmm accumulates problem determination information at specific module points in the form of trace data, and it records this data in main storage. At predetermined intervals, the trace data is scheduled for output to DASD. The DFSMSrmm trace recording function receives the trace data scheduled for output and writes this data to a file on DASD. The PDA facility consists of two separate log data sets. DFSMSrmm recognizes these log data sets by their DD names, EDGPDOX and EDGPDOY. Recording takes place in the data set defined by EDGPDOX. When that data set is filled, the two data set names are swapped, and recording continues on the newly renamed data set.

When this data set is filled, the names are again swapped, and the output switches to the other data set, thus overlaying the previously recorded data. The larger the data sets, the longer the period of time that is represented by the accumulated data.

Establish a procedure that automatically copies the EDGPDOY data set to tape as a generation-data-group data set each time DFSMSrmm issues message EDG9117I. This practice provides a sequential history of trace data over time so that the data is available when needed for resolving problems.

DFSMSrmm trace data can be formatted with the DFSMShsm ARCPRPDO utility. You are authorized to use ARCPRPDO even if you are not licensed to use DFSMShsm. See z/OS DFSMShsm Diagnosis for details about ARCPRPDO. z/OS DFSMSrmm Diagnosis Guide provides information about using the DFSMSrmm trace data to determine possible sources of errors. See z/OS MVS System Messages, Vol 1 (ABA-AOM) and z/OS MVS System Messages, Vol 2 (ARC-ASA) for the messages issued by the DFSMShsm ARCPRPDO utility.