[8u] RFR 8233197: Invert JvmtiExport::post_vm_initialized() and Jfr:on_vm_start() start-up order for correct option parsing

[Mario Torre]

On Wed, Jun 3, 2020 at 4:25 PM Andrew Haley <aph at redhat.com> wrote:
>
> On 03/06/2020 08:52, Jaroslav Bachorík wrote:
> > BTW, since this patch missed the cutoff date for 8u262 mostly due to
> > review would it be ok to consider it still as a part of the critical
> > fix process?
>
> Yes, but why is "Without this patch JVM will crash if a recording is
> started from agent premain" important? Is that something that
> frequently happens?

I'll let Jaroslav discuss the use case in details, but some tools that
retrieve system performance statistics may want to install themselves
via an agent. I think requiring the JFR subsystem to be available only
after pre-main is a bug, JFR should be there at JVM startup already,
or, in the worst case, not be available but also not core dump the
jvm.

Cheers,
Mario

-- 
Mario Torre
Associate Manager, Software Engineering
Red Hat GmbH <https://www.redhat.com>
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