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shenandoah

Can't use Shenandoah GC

I can't put ShenandoahGC to work while trying to run a Java application. Regardless of what I try, the output is as follows, when invoking the java command from Terminal (or CMD): Error occurred during initialization of VM Option -XX:+UseShenandoahGC not supported Running openJDK version 15.0.2 on Ubuntu (WSL) and on Windows, I get the same message on both. Have tried applying the -XX:+UnlockExperimentalVMOptions option next to -XX:+UseShenandoahGC, but as far as I know the experimental status was dropped with JDK 15.

2022-05-02 02:51:45    分类:问答    java   garbage-collection   shenandoah

Shenandoah 2.0 elimination of forwarding pointer

In Shenandoah 1.0 every single Object had an additional header - called forwarding pointer. Why was that needed and what is the reason that lead to its elimination in Shenandoah 2.0?

2021-08-11 01:11:51    分类:问答    java   garbage-collection   jvm   shenandoah

Shenandoah Garbage Collector Load Reference Barriers

It is not a big secret for people who have watched the development of Shenandoah that a major criticism is that it employs GC barriers for every single write and read : be it reference or primitive. Shenandoah 2.0 claims that this is not a problem anymore and it is solved via so-called load reference barriers. How is this exactly happening?

2021-05-14 18:44:36    分类:问答    java   garbage-collection   jvm   shenandoah