Review request for JMC-6492: Add unit support for jdk.jfr.Frequency

[Alex Macdonald]

Hi Jie,

On Wed, May 29, 2019 at 9:36 AM Jie Kang <jkang at redhat.com> wrote:

> Hi,
>
> The attached patch adds a case for contentType "hertz",  annotation
> "jdk.jfr.Frequency" used in JFR events like CPUTimeStampCounter, to
> use the Hertz unit introduced in JMC-5768.
>
> The following is a before and after image for the event browser for
> CPUTimeStampCounter
> https://imgur.com/a/cSVlmOM
>
> How does it look?
>

This looks good to me.

Just a note from playing around with the patch, CPUTimeStampCounter was
updated in changeset 2cf5bec8d8ba [0] to use hertz instead of frequency per
second. As a result, older recordings will still show their numerical value
as per their jfr file, but newer recordings will now correctly use the hz
unit.


>
>
> Regards,
>

Cheers,

Alex

[0] http://hg.openjdk.java.net/jdk-updates/jdk11u/rev/2cf5bec8d8ba