RFR: 8367473: Shenandoah: Make the detailed evacuation metrics a runtime diagnostic option

[Rui Li]

On Thu, 11 Sep 2025 22:43:23 GMT, William Kemper <wkemper at openjdk.org> wrote:

> Non-product builds currently have a feature to produce detailed metrics about evacuations (number of objects, number of bytes, split out by age (young, old, promotion) and thread (mutator or worker). This change makes this feature accessible in release builds as a diagnostic option.

This print might also need to be sandwiched by the `ShenandoahEvacTracking` flag check? https://github.com/openjdk/jdk/blob/master/src/hotspot/share/gc/shenandoah/shenandoahGenerationalControlThread.cpp#L332-L333

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

PR Comment: https://git.openjdk.org/jdk/pull/27238#issuecomment-3294824583