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

Tue Apr 23 21:16:29 UTC 2024

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 know 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)

Looks good.

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Marked as reviewed by kvn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/18864#pullrequestreview-2018311795