RFR: 8330677: Add Per-Compilation memory usage to JFR

[Thomas Stuefe]

On Fri, 26 Apr 2024 08:06:14 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> We have the (opt-in, disabled by default) compiler memory statistics introduced with [JDK-8317683](https://bugs.openjdk.org/browse/JDK-8317683).
>> 
>> Since temporary memory usage by compilers can significantly affect process footprint, it would make sense to expose at least the total peak usage per compilation via JFR.
>> 
>> --- 
>> 
>> This patch adds "Arena Usage" to CompilationEvent. We now see in JMC how costly a compilation had been. (The cost can get very high, as we have seen just recently again with [JDK-8327247](https://bugs.openjdk.org/browse/JDK-8327247) ).
>> 
>> ![jmc-memstat](https://github.com/openjdk/jdk/assets/6041414/8cac366a-2a8f-45ca-be40-d419712f81a7)
>
>> We have the (opt-in, disabled by default)
> 
> Might be helpful to add to the Description part of https://bugs.openjdk.org/browse/JDK-8317683 another sentence that describes how to enable the feature.

Thanks @MBaesken . Please check again to see if I addressed all your issues.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/18864#issuecomment-2079305078