Key Insights from the z/OS Deep Dive Series: A System Support Perspective

The IBM Z Deep Dive Series is a monthly, practitioner-focused technical webinar series designed to help professionals deepen their expertise in IBM Z technologies. Each session focuses on a specific technology topic and brings together subject matter experts through engaging and interactive discussions.

I recently attended the z/OS Deep Dive, the very first edition of this series, and wanted to share my key takeaways and how I plan to apply what I learned.

Why I Joined This Session

I joined this Deep Dive session because keeping up with z/OS evolution is a core part of my role as System Support for IBM Z. I work closely with development teams on a daily basis, and understanding what's new on the platform helps me provide better guidance and anticipate their needs. I was particularly interested in learning about the latest z/OS 3.2 capabilities and any tools that could make our support activities more efficient.

I watched all six sessions on replay, which gave me the flexibility to focus on the topics most relevant to my work.

Key Highlights

Highlight #1: z/OS 3.2 Brings a Wealth of Practical Enhancements

The "What's New in z/OS 3.2" session was a real fire hose of information. What struck me most is how many of these enhancements are delivered through continuous delivery, meaning some are already available on z/OS 2.5 and 3.1 via APARs. Among the highlights: ZCX 2.0 is now freely entitled, the Open XL C/C++ compiler is available at no additional charge, and tools like Python, Ansible, and ZOAU continue to be freely available as bypassable requisites. For teams supporting developers, this is great news because it lowers the barrier to adopting modern tooling on z/OS.

Highlight #2: WLM Policy Advisor, A Practical Tool for Everyday Optimization

The session on the WLM Policy Advisor in z/OSMF was immediately actionable. The tool analyzes your WLM service definition against real SMF type 72 performance data and highlights unused service classes, missing classification rules, and suboptimal goal definitions. The recommendation to keep no more than 25 to 35 active service class periods and to prefer percentile response time goals over average response time goals were clear, practical guidelines that any support team can apply right away. The heat map visualization of performance indexes across time is a powerful way to spot issues at a glance.

Highlight #3: Free Modernization Tools Are Ready to Use

One recurring theme across several sessions was how much IBM is investing in making the platform more open and accessible. Easy NoSQL now supports COBOL in addition to C, Java, and Python. PySDSF lets you interact with SDSF from Python scripts. The JES2 JSON-based policy definitions reduce the need for assembler exits. For someone in a support role, these are concrete steps that make it easier to help developers adopt z/OS without requiring them to learn legacy interfaces first.

Technical Deep Dive

Here are three technical concepts that stood out to me:

WLM Policy Advisor workflow. The advisor loads SMF data sets, scans for available policies and systems, and presents findings with actionable recommendations. You can review unused service classes, check for work running in SysOther (indicating missing classification rules), and examine response time distributions per service class period. Everything is accessible from the z/OSMF WLM task. 

RACF User ID Containment. A new security capability that goes beyond simply revoking a user ID. When an anomalous user ID is detected, it can be placed in a containment list where every SAF call is rejected immediately, stopping all activity from that ID across the system. Combined with IBM Z Threat Detection, this creates a detect-and-contain workflow that is far more effective than traditional revoke or cancel approaches.

What I Plan to Apply

After attending this Deep Dive, I would also like to explore PySDSF and the free modernization tools more broadly. Being able to script SDSF operations in Python opens up interesting possibilities for automating routine support tasks like browsing sysout or reading the operlog.

Community Experience

One of the most valuable parts of the IBM Z Deep Dive Series is the opportunity to connect with others in the community and learn from different perspectives.

As someone working in system support, I find these sessions valuable not just for the technical content, but also for understanding what other organizations are doing and what questions they're asking. It helps me benchmark our own practices and identify areas where we can improve.

Looking Ahead

I'm looking forward to the next IBM Z Deep Dive session on IMS, scheduled for June 17, 2026, and continuing to learn alongside the IBM Z community. Register here : https://ibm.biz/ZDeepDive

I still need to complete the steps to earn my IBM Z Deep Dive badge, which is on my to-do list. If you haven't attended yet, I'd recommend starting with the replays. The content is well worth your time.