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

[Matthias Baesken]

On Fri, 19 Apr 2024 13:12:21 GMT, Thomas Stuefe <stuefe 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)

Please also check COPYRIGHT years, e.g. compileTask.cpp .
Could you also check if there is an easy way to enhance some existing test for the JFR Compilation event. always good to have at least some basic testing .

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PR Comment: https://git.openjdk.org/jdk/pull/18864#issuecomment-2078758555