RFR: 8266723: JFR periodic events are causing extra allocations

[Thomas Stüfe]

On Mon, May 17, 2021 at 2:11 PM Andrew Dinn <adinn at redhat.com> wrote:

>
> On 17/05/2021 12:44, Jaroslav Bachorík wrote:
> > JDK 11 has the full implementation of JVM logging and the
> > 'should_log()' implementation is based on it.
>
> >> One small point, is it not excessive to always dive into native
> >> coding for querying the log state? How hot is this coding? Ideally
> >> logging should not cause overhead if logging is disabled. Would it not
> >> be sufficient to cache the value in java?
> >
> > Good point. I will add caching.
> That first statement makes me wonder about the need for this? Is the log
> setting also cached in jdk11? If not then I wonder whether this is
> really needed.
>
>
I agree, we should have the same solution in both releases.

Wrt caching, logging can be switched off and on via jcmd, so caching is a
trade off function wise. That's why I asked how hot the code is.

Cheers, Thomas


> regards,
>
>
> Andrew Dinn
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