Chapter 5 Further Reading: z/OS Workload Manager
IBM Official Documentation
z/OS MVS Planning: Workload Management
IBM Publication Number: SA23-1390 (updated with each z/OS release) URL: https://www.ibm.com/docs/en/zos/latest?topic=zos-mvs-planning-workload-management
The definitive reference for WLM configuration and design. Chapter 2 (Defining Service Goals) and Chapter 3 (Defining Classification Rules) are essential reading for architects. The examples use the ISPF panel format you will encounter in production. Dense but authoritative — keep this bookmarked as your primary WLM reference.
z/OS MVS Programming: Workload Management Services
IBM Publication Number: SA23-1391
The programming interface guide for WLM. Relevant if you are writing tools that interact with WLM programmatically — for example, a COBOL program that queries WLM service class status or a utility that processes SMF type 72 records. Chapter 4 covers the WLM API (IWMQRSC, IWMQWRK macros). Most architects do not need this level of detail, but it is invaluable for building custom monitoring tools.
z/OS Resource Measurement Facility (RMF) User's Guide
IBM Publication Number: SC34-2664
The RMF reporting reference. Chapter 6 covers the Workload Activity Report in detail, including field definitions, calculation methods, and interpretation guidelines. The examples show how to read and analyze the reports discussed in Section 5.7. If you are responsible for WLM performance analysis, this is required reading.
z/OS MVS System Management Facilities (SMF)
IBM Publication Number: SA38-0667
The SMF record reference. Chapter on Record Type 72 documents the exact layout of WLM-related SMF records, including all subtypes (3, 4, 5). Essential if you are writing COBOL or REXX programs to process SMF data for custom performance reports or capacity planning feeds.
IBM Redbooks
ABCs of z/OS System Programming — Volume 10: WLM
IBM Redbook: SG24-6990
The most accessible introduction to WLM for practitioners. Walks through service definition design with real-world examples and ISPF panel screenshots. The chapter on service class period design is particularly well done. Recommended as your first deep-dive after this textbook chapter. Approximately 200 pages, readable in a weekend.
System Programmer's Guide to: Workload Manager
IBM Redbook: SG24-6472
A more advanced treatment focused on the system programmer's perspective. Covers WLM internals, the relationship between WLM and the z/OS dispatcher, and advanced topics like WLM resource groups and scheduling environments. The section on WLM in a Parallel Sysplex environment is excellent for architects working in multi-system environments. This is the Redbook Kwame Mensah credits as the foundation of his WLM expertise.
z/OS Performance: Monitoring and Tuning with RMF
IBM Redbook: SG24-6059
Focuses on using RMF for performance analysis, with significant WLM coverage. Chapters 4 and 5 show how to use RMF Monitor III reports for real-time WLM analysis. Includes practical examples of diagnosing common WLM performance issues. The batch performance chapter is directly applicable to the scenarios discussed in Sections 5.5 and 5.7.
SHARE and Industry Conference Presentations
"WLM Best Practices for the Modern Mainframe" — SHARE Conference
Multiple presenters have covered this topic at SHARE (the premier mainframe user group conference). Search the SHARE proceedings archive for recent presentations. Key topics to look for:
- Service definition design patterns for hybrid workloads (online + batch + API)
- WLM and zCX container integration
- WLM in cloud-connected mainframe environments
- Performance Index trending and capacity planning
SHARE presentations tend to be highly practical, with real-world examples from production shops. Many include before-and-after metrics similar to the CNB case study in this chapter.
URL: https://www.share.org/proceedings
"Practical WLM: What I Wish I'd Known" — Various CMG Presentations
The Computer Measurement Group (CMG) conferences frequently feature WLM-related presentations from capacity planning professionals. These tend to be more quantitative than SHARE presentations, with detailed performance data analysis. Search for:
- WLM goal-setting methodology
- Service class period tuning
- SMF type 72 analysis techniques
- Batch window optimization strategies
URL: https://www.cmg.org/
Books
z/OS Performance and Capacity Management
Author: David Bowen A comprehensive text on z/OS performance management with strong WLM coverage. Chapter on WLM design methodology provides a structured approach to creating service definitions from scratch — complementary to the principles in Section 5.8. The capacity planning integration chapters connect WLM data to hardware procurement decisions.
MVS Performance Management: WLM and Beyond
Author: Various (IBM Press) An older but still valuable text that covers the transition from compatibility mode to goal mode. The historical perspective is useful for understanding why WLM works the way it does. The design patterns chapter presents templates for common workload configurations (banking, insurance, government, retail) that you can adapt for your environment.
Online Resources
IBM Z Content Solutions: Workload Management
URL: https://www.ibm.com/support/z-content-solutions/workload-management/
IBM's curated collection of WLM resources, including documentation links, Redbook references, and technical articles. A good starting point when you need to find a specific piece of WLM documentation quickly.
Mainframe Performance Topics Blog
URL: https://mainframeperformancetopics.com/ (community blog)
Community-driven blog that regularly covers WLM topics with practical examples. The posts on WLM for batch-heavy environments and WLM governance are directly relevant to the FBA case study in this chapter. Comments sections often include insights from experienced practitioners.
IBM Z and LinuxONE Community
URL: https://community.ibm.com/community/user/ibmz-and-linuxone/
The IBM community forum for z/OS topics. The "Performance and WLM" subforum is an active resource where practitioners discuss real-world WLM challenges. Kwame Mensah (CNB) is a regular contributor. Useful for troubleshooting specific WLM configuration questions.
Vendor Tools for WLM Analysis
IntelliMagic Vision for z/OS
A commercial performance analytics platform that processes SMF data (including type 72) into dashboards and trend reports. Provides automated WLM analysis with anomaly detection and capacity forecasting. Used by many large mainframe shops, including CNB, for the kind of trend analysis discussed in Section 5.7.
BMC MainView for z/OS
A real-time performance monitoring tool with extensive WLM visualization. Provides real-time service class performance dashboards, PI trending, and alert capabilities. The WLM Advisor feature recommends service definition changes based on observed performance patterns.
Broadcom MICS (formerly CA MICS)
A historical performance data warehouse that processes SMF records into a relational database for trending and capacity planning. The WLM data model supports the kind of multi-month PI trend analysis that Lisa Tran performs at CNB.
Recommended Reading Order
For a COBOL architect new to WLM, the recommended reading sequence is:
- This chapter — conceptual foundation and architectural perspective
- ABCs of z/OS System Programming Vol. 10 — hands-on ISPF panel walkthrough
- z/OS MVS Planning: Workload Management (Chapters 2-4) — detailed configuration reference
- RMF User's Guide (Chapter 6) — learning to read WLM reports
- System Programmer's Guide to: Workload Manager — advanced topics
- SHARE/CMG presentations — real-world patterns and case studies
Total investment: approximately 40-60 hours of study to reach proficiency. WLM is one of those topics where the learning curve is steep but the payoff is enormous — understanding WLM transforms you from a developer who writes code to an architect who understands how that code performs in the context of an enterprise system.