24.05.0.0

April 2024 PSU release security fixes.

The default value of -XX:ProfileStartupLimitInSeconds has changed from 60 to 0. This follows from a previous change where 0 was changed from "infinite" to actually 0 seconds. For more information on ProfileStartupLimitInSeconds, see Command Line Options, Advanced Miscellaneous Options.

Azul Zing 24.05.0.0 implements some behavioral changes to the command line option VMFootprintLevel. In order to reduce memory footprint, malloc arenas now use half the number of CPU cores when setting a non-default value of VMFootprintLevel; L, M, or S

The minimum value supported for Xms (initial heap size) was lowered drastically from 512 MB to 128 MB. Previously, the minimum supported Xms was 512 MB. The minimum supported Xmx (maximum heap size) remains unchanged at 512 MB. The purpose of this change is to reduce memory consumption from small utility processes which don’t require a high amount of memory.

Azul Zing 24.05.0.0 introduces a new command line option, -XX:ThpDisable, which can be used to disable Transparent Huge Pages (THP) in the entire JVM process, even when system THP settings are enabled. When -XX:+ThpDisable is set, THP is turned off, overriding the system default.

Azul Zing 24.05.0.0 is now able to collect Falcon diagnostics during OOM (Out of memory) errors.

Thread-local backoff for secondary_super_cache updates has been ported from OpenJDK, based on JDK-8316180 and is disabled by default. To enable this feature, use the option -XX:SecondarySuperMissBackoff=1000.

A new command line option, OptimizeIdentityHashForDistribution has been introduced in Zing 24.05.0.0. This option enables an alternate implementation for System.identityHashCode() which provides better distribution of objects at the cost of making the identity hash calculation itself slower. This option is disabled by default and can be enabled using -XX:+OptimizeIdentityHashForDistribution.

There are no new issues to report in this release.