If I run these tests in a loop with these options:

-XX:+UseZGC -Xmx2g -XX:ZCollectionInterval=0.01

They get com.sun.jdi.ObjectCollectedException intermittently here:

com.sun.jdi.ObjectCollectedException
        at jdk.jdi/com.sun.tools.jdi.JDWPException.toJDIException(JDWPException.java:55)
        at jdk.jdi/com.sun.tools.jdi.ArrayReferenceImpl.length(ArrayReferenceImpl.java:70)
        at nsk.jdi.ArrayType.newInstance.newinstance002.runThis(newinstance002.java:226)
        at nsk.jdi.ArrayType.newInstance.newinstance002.run(newinstance002.java:81)
        at nsk.jdi.ArrayType.newInstance.newinstance002.main(newinstance002.java:76)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:564)
        at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
        at java.base/java.lang.Thread.run(Thread.java:832)


I don't know if this is a ZGC problem or a test problem. In the source code, it doesn't look like the array should be collected, so I'm starting it with ZGC.

I'm linking to an old issue that might not be relevant but did get an OOM once, so might be helpful.