Some Under-the-Radar Db2 13 for z/OS Features to Consider

Db2 13 for z/OS has been available for some time now, and soon (December 2025) it will be the only version of Db2 supported by IBM. So, we all should be either using Db2 13 already, or well into the process of migrating to Db2 13.

With that in mind, here are a few a lesser-known but compelling new features in Db2 13 for z/OS. That is, these enhancements have not received as much attention as the more news-hogging AI and performance new features. 

Online Removal of Active Log Datasets 

1. Remove Active Log Datasets While Db2 Is Running

It is now possible to remove active log data sets while Db2 is up and running. This new capability is available in Function Level 500 and above. This can be accomplished using 

–SET LOG REMOVELOG 

Using this new option of the -SET LOG allows you to safely remove an active log data set from the BSDS without requiring downtime—as long as the data set isn't currently in use.

• If the data set is in use, the data set will be placed in a “REMOVAL PENDING” state, making it unavailable moving forward, until explicitly handled.

• If it's the next log to be written, the command fails with “REMOVAL PROHIBITED.”

• You can monitor this using -DISPLAY LOG DETAIL and use D GRS,RES=(*,dsname,*) to check log usage.

This feature greatly reduces operational risk and complexity during log maintenance in active environments.

DDL Lock Management

Db2 13 adds several new controls that help improve availability and reduce contention when performing DDL (data definition) operations:

• CURRENT LOCK TIMEOUT special register: Lets you override the system-level lock timeout (IRLMRWT) on a per-statement basis (values from 1–32767 seconds), limiting how long transactions queue behind DDL.

• DEADLOCK_RESOLUTION_PRIORITY global variable: Assigns a numerical priority (0–255) to help determine which process is likely to win in a deadlock. Higher values make a DDL process less likely to be chosen as a deadlock victim.

• System monitor profiles can now be configured — for both local and remote applications — to automatically set these values and even adjust package release behavior between RELEASE(COMMIT) and RELEASE(DEALLOCATE).

These features provide more granular control over lock management and thereby should help us reduce disruptions, improve the responsiveness of DDL, and help maintain service levels across transactional workloads.

Why These Features Deserve More Spotlight

• Operational impact without fanfare: While AI functions and accelerator improvements grab headlines, these enhancements quietly deliver high-impact capabilities—especially in high-availability, non-stop environments.

• Prevents outages during routine tasks: The ability to remove log datasets live and better manage DDL locking improves reliability and uptime for critical systems.

• Real-world value for DBAs and sysprogs: These are features that seasoned Db2 for z/OS professionals will deeply appreciate—and can use to simplify otherwise risky operations.

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Bonus: Other Less-Heralded, but Useful Enhancements

From the 2024 continuous delivery updates (without function-level control), these two new capabilities also seem to be flying under the radar:

• Database utilities running on zIIP: APAR PH63832 allows portions of the COPY utility to leverage zIIP processing, reducing CPU costs.

• Targeted statistics deletion: APAR PH63145 lets you delete catalog statistics for a specific partition—without touching the whole object.

Maybe I have missed your favorite under the rader Db2 13 enhancement? If so, please share it with the community in a comment below!