The new runtime environment for Java, IBM® 64-bit Runtime Environment for z/TPF, Java™ Technology Edition, Version 8.0-5.5 contains several enhancements. The runtime environment has been updated to recognize the IBM z14™ (z14) mainframe and optimize your Java applications for the z14 architecture. As part of running your Java application, the runtime environment automatically detects which mainframe model your system is running on and optimizes your application for that architecture. With this update, runtime environment for z/TPF includes support for the IBM zEnterprise EC12 (zEC12), the IBM z13® (z13®), and now the z14 as well.
In addition, the runtime environment has been updated for Dynamic CPU Capacity support (APAR PJ44591). When the number of available I-streams changes due to HiperDispatch or a changed I-stream cap, the IBM J9 virtual machine (JVM) automatically moves off unavailable I-streams (collapsed I-streams) or moves to newly available I-streams (expanded I-streams). This allows long running JVMs to react to changes in the number of in-use I-streams without having to stop and restart the JVM. Also, some JVM processing, like garbage collection, uses the number of I-streams to determine how many threads (ECBs) to use when starting work. The JVM has been changed to use the number of currently in-use I-streams (I-streams that can accept work) instead of the number of active I-streams (physically available I-streams).
Finally, enhancements to the runtime environment allow improved startup performance when starting the JVM on your z/TPF system.
Updates made to the IBM® 64-bit Runtime Environment for z/TPF, Java™ Technology Edition, Version 8 also address various defects and product security vulnerabilities. For more information on the product security vulnerabilities, see the security bulletin. Download and install the PJ44968_ibm-java-jre-8.0-5.5 package from the IBM 64-bit Runtime Environment for z/TPF, Java Technology Edition, Version 8 download page.
The updates to z/TPF support for Java (APAR PJ44968) provide enhancements and address various defects and are designed to work with updates made to the IBM® 64-bit Runtime Environment for z/TPF, Java™ Technology Edition, Version 8.0-5.5. For more information about APAR PJ44968, see the APEDIT.
Apply both updates (the runtime environment download package and APAR PJ44968) to your z/TPF system at the same time.