Mainframe, MVS and zOS Discussion

I would keep JES spool retention short and handle long-term retention separately. If particular SYSOUT is needed for audit or later investigation, copy it to a managed data set or output archive, verify that it can be retrieved, and then purge the spool copy.

The retention period can then vary by ...

I would start with SMF 30 subtype 4 at the job-step level - subtype 5 can hide which step caused the increase. Compare the affected run with a normal run using SMF30CPT and SMF30CPS, along with zIIP time, elapsed time, EXCP count and input volume.

If the step genuinely consumed more CPU, I would ...

If I have understood the question correctly, are you trying to use CI/CD to execute regular application batch JCL, or is this JCL performing build, deployment or automated testing activities?CI/CD is suitable for the latter - for example, compile/link-edit, DB2 bind, deployment and regression-test ...

If I have understood the question correctly, these are not exactly alternatives, as they address different requirements.

For a scheduler-submitted job, the scheduler normally runs under its own RACF ID and is authorized through RACF, commonly using SURROGAT, to submit the job under an application ...

A 3-minute versus 30-minute SORT usually indicates a resource wait, but first confirm that both runs processed the same amount of data with the same SORT statements and allocations.As an application programmer, compare one fast and one slow run for:

Step CPU time versus elapsed time
EXCP count ...

Checkpoint/restart is a broad subject, and the implementation depends heavily on what the program is processing.At a high level, a checkpoint marks a known consistent point up to which processing has completed successfully. A restart restores the application to that point and continues without ...

MFED uses the Micro Focus COBOL compiler, while z/OS normally uses IBM Enterprise COBOL. MFED provides strong mainframe compatibility, but the two compilers are not identical. The first things to compare are:

COBOL dialect: MFED may accept Micro Focus extensions or tolerate syntax that IBM ...

There’s definitely a lot of noise around tools like Claude, but calling them a “threat” to the mainframe ecosystem is an overstatement. What they do change is the economics of modernization , not the relevance of mainframes themselves.

Mainframes continue to run critical, high-volume, high ...

You’re actually in a stronger position than most “pure” mainframers . I wouldn’t present this as returning to mainframe — instead, position yourself as someone who understands both legacy (COBOL/CICS/DB2, etc.) and modern web/cloud architectures. That combination is exactly what most organizations ...

Happy Republic Day.

Welcome to the forum Pablo-Fuentes, great to have you here!

It’s a great question — and in many cases, the perceived complexity is actually larger than the real effort involved. COBOL and REXX already have mature ways to invoke REST services today, whether through the z/OS Client Web Enablement ...

Hello.

I'm not familiar with Rocket Git...

Rocket Git for z/OS is Rocket Software’s port of the popular Git version control system to the IBM mainframe environment. It gives mainframe developers the same benefits that distributed developers enjoy with Git—tracking changes, managing versions ...

Hi,

Git push failing with large COBOL copybooks. We are using Rocket Git and it timeouts with big copybooks. What are the Workarounds? Could someone please guide.

This usually happens because very large COBOL copybooks (often flattened or vendor-supplied) make the Git pack huge, and git push ...

Yes, this is a common pain point when moving to CI/CD with DBB + Jenkins — especially if multiple builds try to touch the same copybooks or loadlibs at once. A few approaches I’ve seen work in practice:

Isolated workspaces per build:

Each Jenkins executor uses its own dedicated directory for ...

JES2 can’t give a system two primary node names at the same time. For a smooth migration, keep the old local name initially, and on all three systems define both the old and the new names as remote nodes pointing to the same partner. That lets you run old and new routes in parallel. When ready ...

The simplest answer is: ask IBM, especially if you’re evaluating one of their own product offerings.- Putting it into context - yes, ZD&T is worth considering for development and testing environments, particularly when the objective is cost control without compromising developer agility. It gives ...

FASYMLIB (Fast Symbolic Library) is a dataset used in mainframe environments—especially with CA Endevor —to store and manage symbolic variables that are substituted dynamically during processes like compiling, linking, or deploying programs. It helps control environment-specific values such as ...

Happy Republic Day India!

The KEEP and PASS parameters in JCL are used in the disposition ( DISP ) of a dataset. While they may appear similar at first glance, they have distinct behaviors, particularly when dealing with temporary datasets versus permanent datasets .

1. KEEP Disposition

Purpose: Retains the dataset ...

Just adding my two cents: Wouldn't JCICS require the Java program to run within the same mainframe environment where CICS and the VSAM datasets reside? As far as I know, JCICS enables Java applications to interact with CICS, but this typically happens within the JVM running on z/OS. Since the OP ...