The newly added test gc/shenandoah/mxbeans/TestPauseNotifications.java#generational intermittent trigger assert which observed from GHA https://github.com/sendaoYan/jdk-ysd/actions/runs/12253929063/job/34186348381, the test log snippet:

Received: Shenandoah Cycles/end of GC cycle
Warning: [0.987s][warning][gc,free] Forcing transfer of 502 to old reserve.
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# A fatal error has been detected by the Java Runtime Environment:
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# Internal Error (d:\a\jdk-ysd\jdk-ysd\src\hotspot\share\gc\shenandoah\shenandoahGeneration.cpp:1029), pid=1676, tid=5312
# assert(ShenandoahHeap::heap()->is_full_gc_in_progress() || (_affiliated_region_count * ShenandoahHeapRegion::region_size_bytes() <= _max_capacity)) failed: Cannot use more than capacity
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# JRE version: OpenJDK Runtime Environment (25.0) (fastdebug build 25-internal-sendaoYan-110539b0ac5abe0444e437f6e37f2e1c51b2be38)
# Java VM: OpenJDK 64-Bit Server VM (fastdebug 25-internal-sendaoYan-110539b0ac5abe0444e437f6e37f2e1c51b2be38, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, shenandoah gc, windows-amd64)
# Problematic frame:
# V [jvm.dll+0xee646b] ShenandoahGeneration::decrease_capacity+0x14b
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# CreateCoredumpOnCrash turned off, no core file dumped
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# An error report file with more information is saved as:
# D:\a\jdk-ysd\jdk-ysd\build\run-test-prebuilt\test-support\jtreg_test_hotspot_jtreg_tier1_gc\scratch_1\hs_err_pid1676.log
Warning: [1.136s][warning][os ] Loading hsdis library failed
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# If you would like to submit a bug report, please visit:
# https://bugreport.java.com/bugreport/crash.jsp