Cheryl Watson’s Tuning Letter
A Planet Mainframe Brand
2026 Tuning Letters
No. 1 (93 pages)
Welcome to the latest edition of the Cheryl Watson's Tuning Letter
SHARE Orlando Recap
General Musings
Squeezing Even More Throughput Out of CICS
Threadsafe
Squeezing more work out of CICS
Spreading the word
A Coffee Date with Db2
Db2 trace records
Classes
Instrumentation Facility Component IDs
Back To The Future: From The Archives | Top 10 Findings from z/OS Security Assessments - Part 2
A decade of z/OS Security Assessments
Remediation for Vertali’s Top 13 Security Assessment Findings of the 2020’s
Closing
References
TADz for the Systems Programmer
Introduction
IBM Tivoli Asset Discovery for z/OS
The background
So what happened next?
Product Use Trend Job Names
Discover Product Detail
To conclude
IPL What the heck is that???
Bootstrap Module
IRIMs Tasks
System Component Address Spaces
Types of IPLs
The LOADxx Member
LOAD Parm Processing
IPLTEXT Processing
Summary
Security hints and tips—Operational security is a behaviour, not a product
Understanding before controls
Treating change as a risk multiplier
Security as a collaboration problem
Clarity as a security control
Learning out loud
Let me be Frank
Preserving z/OS excellence through simplification
Why do we need to simplify?
Won’t simplification hide what’s really happening?
Does this mean you are getting rid of JCL?
Are we just making z/OS like other systems?
Let’s build this together
Conferences & Events
- Mighty Mainframe Conference
- GSE BeLux Conference 2025
- IDUG NA 2025 | Atlanta
- GSE Nordic Region Conference 2025
- VM Workshop 2025
- Broadcom Virtual Mainframe Technical Exchange 2025 – Global Virtual Event
- SHARE Cleveland 2025
- IBM TechXchange Conference 2025
- Broadcom Mainframe Technical Exchanges – IDMS & Datacom User Group Workshops
- Broadcom Mainframe Technical Exchanges – North American In-Person Mainframe Technical Exchange
- GS UK In-Person Conference 2025
- Open Mainframe Project – Mainframe Open Education (MOE) Student User Group
New Function APARs
HIPER APARs
Red Alerts
Hardware Alerts
News From Techdocs
No. 2 (108 pages)
Welcome to the latest edition of the Cheryl Watson's Tuning Letter
GS|UK Virtual Conference Recap
Mighty Mainframe Conference
General Musings
Marks Hints and Tips – SMP/e
Mark’s Hints and Tips – Cyber Vault
Share Your Bumps, Bangs, and Mysteries
Let me be Frank
The 3270 Era Is Ending. The Question Is, What Do You Do Next?
3270 is Not the Problem
AI Enters the Picture
It’s All in Your Head
Choose to Engage
The z/OS System Logger - ‘Plan for the worst—hope for the best’
Spidey Senses
1. How to start: run a job like this
2. What types of Logger are there?
3. What about our specific IMS Queue Logger problem?
4. Another interesting thing we found
Appendix 1 — Logstream definition and cheat sheet
Appendix 2 — IXG messages for automation
Appendix 3 — Additional learning
Are you ready for z/OS 3.2? Requirement for the latest version
Storage
SDSF
AI
Z/OSMF
JES2 and WLM
WLM
Hyperswap
Network
Take Note of These Too
Final Thoughts
Is it a file, a data set, or an object?
The z/OS Data Set
The USS file
The Object
Putting it Together
Sysplex Guide to Coupling Facility (CF) Encryption
Introduction
Prerequisites/Readiness Checklist
Overview
Key Storage
Big Picture
Important Considerations
When the AES Master Key Changes
When the Structure Key Changes
Implementation
Troublshooting
Operation
Changing the Encryption Key for a Structure
Terminology (quick definitions)
Old Panel, New Tricks: Getting More from ISPF 3.4
Find a Member
Locate a String in a List of Datasets
Entering Multiple Commands
Appending Datasets to the List
Excluding Datasets from the List
Sorting a Dataset List
Sysprog Stories of Woe— Lessons Learned During a z/OS 2.5 to z/OS 3.2 Migration Preparation
The Background
The Symptom
Why This Matters
Recommended Migration Approach
Additional Recommendations
Final Thoughts
Conferences & Events
New Function APARs
No. 3 (103 pages)
Welcome to the latest edition of the Cheryl Watson's Tuning Letter
General Musings
Nobody likes change
IBM’s nanostack announcement
AI-powered Workload Manager batch initiator management: what’s in it for you?
Background
Benefits analysis
What are the performance metrics measured?
Average Job Queue Time
The anatomy of an abend: what your system dump is actually telling you
The headline: completion code and reason code
The where: PSW and active module
Report: No Active Module Found
The smoking gun: data at the PSW
The registers: context clues
What to do next
The Db2 Corner—Time will tell: Class 3 Wait times
What are service task suspensions?
Datasets open or closed
High Volume Log Writes
A few more
Service Task Suspensions
Lessons learned from a z17 migration: resolving JES2 checkpoint reconfiguration issues
Introduction
The problem
Operational impact
Investigation
IBM recommended resolution
Successful completion
Restoring automatic forwarding
Post-reconfiguration issue
Lessons learned
Conclusion
Let me be Frank
What it means
The Six Categories
The Real Change is Cultural
SMF Record Signing — Internal Implementation Guide
Quick Start (Enable + Validate)
Overview
How SMF signs records (high level)
Step-by-Step Implementation
Create the Artefacts
Verify the Artefacts
Configure SMF
Verify the Installation
Special Considerations
Troubleshooting
Related Ideas
Small Iron: a proper look at the z17 single frame and rack mount announcement
First, a quick refresher on what’s inside a z17
What exactly was announced
The numbers, and what to make of them
Who is this actually for?
The AI story, with a pinch of salt where needed
Security: quietly my favourite part
The software: Terraform on the mainframe, and COBOL gets some love
Dates for your diary
Conclusion