This is a bug reported by Reka Kovacs and she has a proposed fix.

The bug was introduced with the following change:
https://github.com/openjdk/jdk/commit/c3c6662528311d3fd3f29bb0131fc5cfd832183c#diff-1f2f0e53c61691f3feb0f9acb18a8d59f2e066d12c64b1df0832a11536a6b2a4

A snippet of the test output with the error message is shown below:
"Timeout refired 480 times
STDERR:
rerun:
cd /mnt/vss/_work/1/jdk/JTwork/scratch && \
DISPLAY=:1 \
HOME=/home/cloudtest \
JTREG_CONCURRENCY=1 \
JTREG_EXCLUDE_FILES=test/hotspot/jtreg/ProblemList.txt \
JTREG_EXTRA_OPTIONS= \
JTREG_INTERNAL_EXCLUDE_FILES=.devops/problemlist.txt \
JTREG_NATIVE_PATH=hotspot/jtreg/native \
JTREG_TAR=/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmpew201crk/jtreg-5.1-b01.tar.gz \
JTREG_TESTS=test/hotspot/jtreg:tier1_gc \
JTREG_TIMEOUT_FACTOR=4 \
JTREG_VERBOSE=-verbose:fail,error,summary \
LANG=C.UTF-8 \
PATH=/bin:/usr/bin:/usr/sbin \
CLASSPATH=/mnt/vss/_work/1/jdk/JTwork/classes/gc/shenandoah/mxbeans/TestPauseNotifications_id2.d:/mnt/vss/_work/1/jdk/test/hotspot/jtreg/gc/shenandoah/mxbeans:/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmpn86ihphn/jtreg/lib/javatest.jar:/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmpn86ihphn/jtreg/lib/jtreg.jar \
/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmpoa9ivlqa/jdk-17+14/bin/java \
-Dtest.vm.opts=-Xmx512m \
-Dtest.tool.vm.opts=-J-Xmx512m \
-Dtest.compiler.opts= \
-Dtest.java.opts= \
-Dtest.jdk=/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmpoa9ivlqa/jdk-17+14 \
-Dcompile.jdk=/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmpoa9ivlqa/jdk-17+14 \
-Dtest.timeout.factor=4.0 \
-Dtest.nativepath=/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmp2bqfn5sl/jdk-17+14-test-image/hotspot/jtreg/native \
-Dtest.root=/mnt/vss/_work/1/jdk/test/hotspot/jtreg \
-Dtest.name=gc/shenandoah/mxbeans/TestPauseNotifications.java#id2 \
-Dtest.file=/mnt/vss/_work/1/jdk/test/hotspot/jtreg/gc/shenandoah/mxbeans/TestPauseNotifications.java \
-Dtest.src=/mnt/vss/_work/1/jdk/test/hotspot/jtreg/gc/shenandoah/mxbeans \
-Dtest.src.path=/mnt/vss/_work/1/jdk/test/hotspot/jtreg/gc/shenandoah/mxbeans \
-Dtest.classes=/mnt/vss/_work/1/jdk/JTwork/classes/gc/shenandoah/mxbeans/TestPauseNotifications_id2.d \
-Dtest.class.path=/mnt/vss/_work/1/jdk/JTwork/classes/gc/shenandoah/mxbeans/TestPauseNotifications_id2.d \
-Dtest.class.path.prefix=/mnt/vss/_work/1/jdk/JTwork/classes/gc/shenandoah/mxbeans/TestPauseNotifications_id2.d:/mnt/vss/_work/1/jdk/test/hotspot/jtreg/gc/shenandoah/mxbeans \
-Xmx512m \
-Djava.library.path=/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmp2bqfn5sl/jdk-17+14-test-image/hotspot/jtreg/native \
-Xmx128m \
-XX:+UnlockDiagnosticVMOptions \
-XX:+UnlockExperimentalVMOptions \
-XX:+UseShenandoahGC \
-XX:ShenandoahGCHeuristics=adaptive \
com.sun.javatest.regtest.agent.MainWrapper /mnt/vss/_work/1/jdk/JTwork/gc/shenandoah/mxbeans/TestPauseNotifications_id2.d/main.0.jta

TEST RESULT: Error. Program `/mnt/vss/_work/1/openjdk-azure-devops-harness/workspace/tmpoa9ivlqa/jdk-17+14/bin/java' timed out (timeout set to 480000ms, elapsed time including timeout handling was 480251ms)."