RFR(s): 8203682: Add jcmd "VM.classloaders" command to print out class loader hierarchy, details

Kirk Pepperdine kirk at kodewerk.com
Mon May 28 06:46:57 UTC 2018

> On May 28, 2018, at 7:14 AM, Thomas Stüfe <thomas.stuefe at gmail.com> wrote:
> OID - I was not aware that the hotspot had one :)

I guess I sometimes use OID very loosely and interchangeably wth oop.. and I guess I shouldn’t. As you most likely know, in OQL you can run stuff like "select heap.findObject(0x12345ab).parent" so being able to tie in the output from jcmd to a heap dump might be useful.

> AFAIK the only truly unique id of an object is its pointer, the oop
> (which is of course only stable at a safepoint, hence my
> jcmd-safepoint proposal). My command already prints the oop for the
> classloader if sub option "verbose" is given.

Sorry, missed this in the output.

> btw thanks for the positive feedback!

Your welcome.

— Kirk

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