jstack -l -F on shenandoah.

[Zhengyu Gu]

Hi Francisco,

I just pushed a fix for iterating live regions[0], which eliminates the 
warnings.

However, jstack with -F option, seems to take forever to run. I observed 
the same issue with G1. And it seems that -F option is not longer 
supported since jdk11.

Thanks,

-Zhengyu

[0] http://hg.openjdk.java.net/shenandoah/jdk8/hotspot/rev/9c888fe827f2

On 12/2/19 3:10 PM, Francisco De Melo Junior wrote:
> Hello, quick question.
> Does jstack -l -F works with Shenandoah?
> It does seem to work actually, perhaps installing <openjdk-8-dbg> ?
> 
> ~~~
> 
> #jstack -l -F 22424
> Attaching to process ID 22424, please wait...
> Debugger attached successfully.
> Server compiler detected.
> JVM version is 25.232-b09
> Deadlock Detection:
> 
> No deadlocks found.
> 
> Warning: Operation not supported with Shenandoah GC
> Exception in thread "main" java.lang.reflect.InvocationTargetException
>          at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>          at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
>          at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
>          at java.lang.reflect.Method.invoke(Method.java:498)
>          at sun.tools.jstack.JStack.runJStackTool(JStack.java:140)
>          at sun.tools.jstack.JStack.main(JStack.java:106)
> Caused by: sun.jvm.hotspot.types.WrongTypeException: No suitable match
> for type of address 0x0000000002080170
>          at sun.jvm.hotspot.runtime.InstanceConstructor.newWrongTypeException(InstanceConstructor.java:62)
>          at sun.jvm.hotspot.runtime.VirtualBaseConstructor.instantiateWrapperFor(VirtualBaseConstructor.java:109)
>          at sun.jvm.hotspot.oops.Metadata.instantiateWrapperFor(Metadata.java:68)
>          at sun.jvm.hotspot.oops.Oop.getKlassForOopHandle(Oop.java:211)
>          at sun.jvm.hotspot.oops.ObjectHeap.newOop(ObjectHeap.java:252)
>          at sun.jvm.hotspot.oops.ObjectHeap.iterateLiveRegions(ObjectHeap.java:331)
>          at sun.jvm.hotspot.oops.ObjectHeap.iterateSubtypes(ObjectHeap.java:288)
>          at sun.jvm.hotspot.oops.ObjectHeap.iterateObjectsOfKlass(ObjectHeap.java:188)
>          at sun.jvm.hotspot.runtime.ConcurrentLocksPrinter.fillLocks(ConcurrentLocksPrinter.java:70)
>          at sun.jvm.hotspot.runtime.ConcurrentLocksPrinter.<init>(ConcurrentLocksPrinter.java:36)
>          at sun.jvm.hotspot.tools.StackTrace.run(StackTrace.java:71)
>          at sun.jvm.hotspot.tools.StackTrace.run(StackTrace.java:45)
>          at sun.jvm.hotspot.tools.JStack.run(JStack.java:66)
>          at sun.jvm.hotspot.tools.Tool.startInternal(Tool.java:260)
>          at sun.jvm.hotspot.tools.Tool.start(Tool.java:223)
>          at sun.jvm.hotspot.tools.Tool.execute(Tool.java:118)
>          at sun.jvm.hotspot.tools.JStack.main(JStack.java:92)
>          ... 6 more
> [nextgen at nsvuk3ltpf301 cmc-ngwebfe01]$ java -version
> openjdk version "1.8.0_232"
> OpenJDK Runtime Environment (build 1.8.0_232-b09)
> OpenJDK 64-Bit Server VM (build 25.232-b09, mixed mode)
> ~~~
>