JFR sampling question

[Thomas Stüfe]

Thank you Erik, that is exactly what I needed.

On Wed, Nov 4, 2020 at 1:13 PM Erik Gahlin <erik.gahlin at oracle.com> wrote:

> Hi Thomas,
>
> I don’t know what the event is called, but you can look at the
> configuration files and the period setting for the event.
>
> https://github.com/openjdk/jdk/tree/master/src/jdk.jfr/share/conf/jfr
>
> Erik
>
> > On 4 Nov 2020, at 13:07, Thomas Stüfe <thomas.stuefe at gmail.com> wrote:
> >
> > Hi,
> >
> > I am currently reworking the Metaspace information shown in JMC, which is
> > outdated after JEP387.
> >
> > How often is this information sampled? How expensive can the sampling
> code
> > get?
> >
> > For example, post-JEP387, the metachunk freelists contain committed as
> well
> > as uncommitted areas. While it may be interesting to know how much area
> is
> > committed, that would require walking the freelists, which could get
> > expensive.
> >
> > Thanks, Thomas
>
>