Diagnosing errors using the Problem Determination Aid Facility

During DFSMSrmm processing, the problem determination aid (PDA) facility gathers diagnostic information about DFSMSrmm’s processing, stores this information in a circular file within storage, and periodically writes it to a circular file on DASD.

A circular file appends data until full; then, starting at the beginning of the file, subsequent incoming data overwrites the data already there. The circular DASD file consists of two data sets, EDGPDOX and EDGPDOY. EDGPDOX is the active data set.

Related Reading: For detailed information on using the problem determination aid or calculating the PDA log data set sizes, refer to z/OS DFSMSrmm Implementation and Customization Guide.

There are several reasons why you will at times want to collect and save PDA trace data. These reasons are most common:

A trace showing DFSMSrmm’s operating history can pinpoint the activity at the time the problem first occurs. This information can be helpful because the time difference between when a problem first occurs and when it is first detected.
A trace can locate points of contention when two separate tasks conflict with one another.
A trace can help you to determine if a suspected DFSMSrmm problem really exists, or if it is an operational error.
You can use traces to supplement dumps when you contact your IBM® support group.

Two very useful functions can help you to extract the exact information you need from the PDA files. By using either or both of the ISPF browse function and DFSMShsm ARCPRPDO (PDA trace formatter) program, you might be able to solve your problem without assistance from IBM support.