Skip to content

CAUTION: This site hosts draft documentation for the next release. For published content of the latest release, visit

What's new in version 0.23.0

The following new features and notable changes since version 0.22.0 are included in this release:

Features and changes

Binaries and supported environments

Eclipse OpenJ9™ release 0.23.0 supports OpenJDK 8, 11, and 15. Binaries are available from the AdoptOpenJDK community at the following links:

To learn more about support for OpenJ9 releases, including OpenJDK levels and platform support, see Supported environments.

-XX:[+|-]PortableSharedCache option behavior update

The -XX:[+|-]PortableSharedCache option is updated to improve the portability of AOT-compiled code further. This update allows AOT-compiled code to be portable across OpenJ9 VMs that use compressed references and have a heap size of 1 MB to 28 GB when this option is enabled. This option might introduce a small (1-2%) steady-state throughput penalty when compressed references are used and the heap size is between 1 MB and 3 GB. See -XX:[+|-]PortableSharedCache for more details about this option.

-XX:[+|-]IdleTuningCompactOnIdle option now inactive

Setting the -XX:[+|-]IdleTuningCompactOnIdle option now has no effect. A compaction is triggered by internal heuristics that look into the number of fragmented pages. Typically there is no need to force a compaction. This option was deprecated in release 0.15.0, and will be removed in the future. See -XX:[+|-]IdleTuningCompactOnIdle for details about this option.

Support for OpenJDK HotSpot options

For compatibility, the following OpenJDK HotSpot options are now supported by OpenJ9:

Extended platform support for the JITServer technology preview

Platform support for the JITServer technology preview is now extended to 64-bit Linux® on IBM Power® systems, and 64-bit Linux on IBM Z® systems. JITServer decouples the JIT compiler from the OpenJ9 VM, freeing up CPU and memory for an application. JITServer runs in its own process, either locally or on a remote machine, where resources can be separately managed. This preview was initially introduced in Eclipse OpenJ9 V0.18.1 for Linux on 64-bit x86 systems. For more information, see JITServer technology (technical preview).

Full release information

To see a complete list of changes between Eclipse OpenJ9 version 0.22.0 and version 0.23.0 releases, see the Release notes.