Problems in z/OS are classified by these symptoms:

• Abend – an error or abnormal end of a program or job.
• Wait or Hang – a coded wait state is loaded or the system or a job appears hung or does not complete.
• Loop – the system or program executes infinitely typically using large or higher amounts of processor resource.
• Incorrout – there is incorrect or missing output from a program or job.
• Performance – processing is using too much system resource and impacting other parts or users of the system, or processes are taking too long.
• Message – an error is reported through a message to the operator or in a log.

When an error occurs, z/OS provides various forms of diagnosis information that contains symptoms. These symptoms can help you with diagnosis and be used in problem source identification (PSI). PSI is the determination of what caused the error based on answers to these questions:

• Why was an abend issued?
• What caused storage to be exhausted?
• Why is the job hung?
• What is causing the job to loop?

This information is designed to help answer these questions and others and make efficient use of your time when diagnosing, searching, and reporting a problem to IBM.

PSI is useful even if the root cause of the problem is not identified. During the process, information and symptoms are gathered to check for a known problem or report a new problem. To ease and expedite problem identification, it is important to provide all the background information available. This includes information about:

• Hardware involved
• System and application software levels
• External symptoms
• Problem impact
• Diagnostic data produced

By providing sufficient information during the first call to IBM or the individual software vendor, you might avoid having to re-create the problem.

The problem diagnostic worksheet contains key information needed to expedite problem resolution. If you are an experienced z/OS system programmer, use the Problem diagnostic worksheet as a reminder of the important information to gather and report. For example:

• Extract the diagnostic data and symptoms
• Build a search argument
• Search for a known problem
• Gather available diagnostic information
• Report a new problem.