Skip to content

What's new in version 0.59.0

The following new features and notable changes since version 0.58.0 are included in this release:

Features and changes

Binaries and supported environments

Eclipse OpenJ9™ release 0.59.0 supports OpenJDK 8, 11, 17, 21, 25, and 26.

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

On AIX systems, LDR_CNTRL is set by default, and the -XX:[+|-]UseMediumPageSize option is used to control this default setting

With the new option, -XX:-UseMediumPageSize, you can now disable the default setting of the LDR_CNTRL environment variable on AIX systems whereby medium page sizes (64 KB) are configured for text, data, stack, and shared memory segments.

For more information, see -XX:[+|-]UseMediumPageSize.

A signal handler optimization feature that was disabled on Windows is enabled again

In the 0.57.0 release, on the Windows platform, a signal handler optimization feature was temporarily disabled by default. The feature was disabled because VM crashes were suspected to be related to an interaction between the Windows control flow guard feature and the VM's signal handling mechanism.

Now the root cause for these VM crashes has been identified and fixed. Therefore, in this release, the disabled signal handler optimization feature is enabled again.

Compiler changes for Linux

Linux x86 64-bit, Linux on POWER® LE 64-bit, and Linux on IBM Z® 64-bit builds on all OpenJDK versions now use the gcc 14.2 compiler.

For more information, see Supported environments.

Start of content that applies to Java 8 (LTS) Start of content that applies to Java 11 (LTS) glibc version is changed to 2.17 on Linux x86 64-bit builds for OpenJDK 8 and 11

For OpenJDK versions 8 and 11, Linux x86 64-bit is now compiled on CentOS 7, modifying the minimum glibc version to 2.17 from 2.12. The VM will fail to start on CentOS 6 from this release onwards. End of content that applies to Java 8 and 11 (LTS)

Start of content that applies to Java 11 (LTS) and later New -XX:StartFlightRecording command-line option is added

Support for the -XX:StartFlightRecording command-line option is now available from this release onwards. Instead of the JDK Flight Recorder (JFR)-related jcmd option, you can now use the -XX:StartFlightRecording command-line option to start the JFR recording in the VM.

The -XX:StartFlightRecording command-line option cannot be used simultaneously with JFR-related jcmd options.

For more information, see -XX:StartFlightRecording.

End of content that applies only to Java 11 and later

Start of content that applies to Java 11 (LTS) and later New JDK Flight Recorder (JFR) events are added in this release

In this release, the following new JFR events are added:

  • GarbageCollection
  • OldGarbageCollection
  • YoungGarbageCollection

For more information, see -XX:[+|-]FlightRecorder. End of content that applies only to Java 11 and later

compact is added by default to the request=<requests> parameter for the jcmd Dump.heap command

When jcmd Dump.heap is used to request a heap dump, the compact option is now added to the dump request by default. The default request for heap dumps is now: request=exclusive+compact+prepwalk.

For more information, see -Xdump suboptions: request=<requests>.

For more information about jcmd, see Java diagnostic command (jcmd) tool.

Known problems and full release information

To see known problems and a complete list of changes between Eclipse OpenJ9 v0.58.0 and v0.59.0 releases, see the Release notes.