z/OS System Services

This course presents the structure and control blocks of the z/OS BCP and system services. It prepares z/OS system programmers to identify potential bottlenecks and performance problems, perform initial error symptom gathering, and identify opportunities and requirements for tailoring a z/OS system.

This course provides the prerequisite information needed for further training in specialized areas such as system measurement, tuning and problem determination.

This course is intended for z/OS system programmers who are responsible for the customization, measurement, tuning, and/or problem determination of z/OS. Subsystem programmers will also benefit.

Before attending this course delegates should have some knowledge of z/OS systems programming. In particular, delegates should be able to:

• Describe the z/OS characteristics of multiprocessing, multiprogramming, virtual storage and paging, and multiple address space/data space architecture.
• Explain how paging and swapping are accomplished through the interaction of real/central, expanded, auxiliary, and virtual storage in a z/OS system.
• Explain the role of the dispatcher, interrupts, SVCs, the program manager, and serialization in managing work in a z/OS system.
• State the role of z/OS software and hardware components in handling an I/O request for data on a direct access storage device.

Our z/OS Systems Programming Introduction provides the perfect level of prerequisite knowledge.

After completing this course, you will be able to:

• Explain the z/OS functions and control blocks necessary to support a task in a multitasking and multiprocessing environment.
• Describe the software and hardware functions that allow a program to interact with programs running in other address spaces, use data in other address spaces, and use data in data spaces.
• Trace the flow of an I/O operation from the initial request in the application program through the completion of data transfer.
• Identify the control blocks that describe the current status of an I/O request.
• Describe the functions of the z/OS Virtual, Real, and Auxiliary Storage Managers.
• Describe the functions performed by the Recovery Termination Manager and recovery management components to minimize failure impact and enhance error correction.
• Select the appropriate IBM publication to provide further technical information (SRLs, Technical Bulletins, Self-study and other z/OS courses).
• Describe the services provided by cross system extended services (XES).
• Identify and explain the purpose of the cache, list, & lock structures.
• Plan the implementation of the global resource serialization STAR environment.

System Introduction
z/OS Review.
z/OS System Components Review.
Introduction to Control Blocks.
Basics of z/Architecture.

Operating Environment Initialization
System Libraries.
Initial Program Load.

Task Management
Task Dispatching.
Service Request Scheduling.
Program Managing.
Serializing Resources.
Supervisor Calls.
Status Saving on Interrupt.

Addressability
Addressability Review.
Cross Memory Services - Addressability to Two Address Spaces.
Extended Addressability to Multiple Spaces.

Input/Output Supervisor
I/O Definition and Initialization.
I/O Request Flow.
I/O Interrupt Flow.
Error Handling.

Storage Management
Storage Management Review.
A Programmer's Use of Storage.
Paging and Swapping.
Coupling Facility Storage.
Exploitation.

Recovery Termination Manager (RTM)
RTM Overview.
Preparing the Environment.
Normal Termination Processing.
Abnormal Termination Processing.
Recovery Management Support.

Job Scheduling