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

[Thomas Stüfe]

On Mon, May 28, 2018 at 8:46 AM, Kirk Pepperdine <kirk at kodewerk.com> wrote:
>
>> 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.

No problem. I was not sure if you maybe refer to another VM
implementation which may have unique object ids.

> 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.

No, I did not know that :)

>
>>
>> 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.

Again, no problem. Thank you for the feedback.

..Thomas

>
>>
>> btw thanks for the positive feedback!
>
> Your welcome.
>
> — Kirk
>