Three tricks to drastically improve the performance of IBM Developer for z/OS

As IBM Developer for zOS gains more features and updates, performance becomes more of an issue, especially for developers with resource constraints on their computer/laptop. I’ve personally spent far too much time waiting on it to come out of a hang. After a few PMR’s and a couple of “AHA” moments, I’ve come up with a list of actions you can take now to improve the performance of IDz.

1. Upgrade to the latest version of IDz. Yes, even IBM says this, but in this case, if you are on version 16.0.0 to 16.0.3, there is a noticeable improvement in performance of version 16.0.5, with IBM making some intentional changes.
2. Change the following workspace preferences:
   – Under Version Control (Team) > Git > Remote Integration: deselect the option “Enable scanning of attribute files for changes”. This is a known hang point.
   – Under General > Capabilities: Disable features you know you are not using, for example CDT (C++ development tooling), or CICS System Administration. Expand various sections and disable ones you know you are not using. This will save those plugins from being loaded into memory.
   – Under General > Startup and Shutdown: Disable plugins you know you are not using. For example, TPF Toolkit Initialization or the IBM C/C++ Tooling for zSeries.
3. Now, this one is a bit more surgery than you may want, but I assure it can be scripted for an automated installation. Replace the default JDK version 11 with JDK version 17. This is found in the IDz installation directory under jdk.
   – Rename the jdk folder to jdk11.
   – Download the IBM JDK (SDK) 17 from https://developer.ibm.com/languages/java/semeru-runtimes/downloads/. Select IBM Semeru Runtime Open Edition. You want Java 17 (LTS) which is long-term support. IBM will officially support IDz running on version 17. This release, while it has some new language features, offers a huge performance improvement.
   – Once downloaded, extract it to a new jdk folder (rename whatever folder it extracts to “jdk”).
   – Copy the new jdk folder into your IDz installation directory.
   – The next time you launch IDz, it should be using the new Java 17 binaries. This has proven to have a significant improvement in performance for me and my customers. Note that I have also used JDK 21, but IBM will not support you on it if you have issues.