Shenandoah not supported in OpenJDK 12-ea ?

[Roman Kennke]

Hi Lennart,

> I just downloaded the the latest OpenJDK 12 EA build (24, dated 2018/12/15) to check if Shenandoah was available.
> 
> On both Linux and MacOS it says:
> 
> Error occurred during initialization of VM
> Option -XX:+UseShenandoahGC not supported
> 
> When invoked with
> 
> java -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -version
> 
> 
> Is this intentional?

This is intentional on Oracle's part. Builds of OpenJDK by Oracle, and
OracleJDK don't contain Shenandoah GC.

Please try out our own nightlies:
https://builds.shipilev.net/openjdk-jdk12/

Alternatively, any other OpenJDK build (e.g. AdoptOpenJDK) will contain
Shenandoah GC.

Thanks and best regards!

Roman


> To check I've got the correct version, I tried (on both Linux and MacOS, same results):
> 
> $ jdk-12/bin/java -version
> openjdk version "12-ea" 2019-03-19
> OpenJDK Runtime Environment (build 12-ea+24)
> OpenJDK 64-Bit Server VM (build 12-ea+24, mixed mode, sharing)
> 
> $ java -XX:+UseShenandoahGC -version
> Error: VM option 'UseShenandoahGC' is experimental and must be enabled via -XX:+UnlockExperimentalVMOptions.
> Error: The unlock option must precede 'UseShenandoahGC'.
> Error: Could not create the Java Virtual Machine.
> Error: A fatal exception has occurred. Program will exit.
> 
> $ java -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -version
> Error occurred during initialization of VM
> Option -XX:+UseShenandoahGC not supported
> 
> 
>