We run into several timeouts on slower machines in our openjdk fastdebug tests in the test java/time/test/java/time/format/TestZoneTextPrinterParser.java .
Timeouts occur on both Linux and Windows.

Stack whne timeout occurs is as follows :

"MainThread" #26 prio=5 os_prio=0 cpu=701818.96ms elapsed=721.04s tid=0x00007fff80573330 nid=3038682 runnable [0x00007fff39a6b000]
   java.lang.Thread.State: RUNNABLE
Thread: 0x00007fff80573330 [0x2e5dda] State: _at_safepoint _at_poll_safepoint 0
   JavaThread state: _thread_blocked
at sun.util.resources.Bundles.findBundleOf(java.base@18.0.0.1-internal/Bundles.java:160)
at sun.util.resources.Bundles.loadBundleOf(java.base@18.0.0.1-internal/Bundles.java:145)
at sun.util.resources.Bundles.of(java.base@18.0.0.1-internal/Bundles.java:106)
at sun.util.resources.LocaleData$1.run(java.base@18.0.0.1-internal/LocaleData.java:185)
at sun.util.resources.LocaleData$1.run(java.base@18.0.0.1-internal/LocaleData.java:182)
at java.security.AccessController.executePrivileged(java.base@18.0.0.1-internal/AccessController.java:776)
at java.security.AccessController.doPrivileged(java.base@18.0.0.1-internal/AccessController.java:318)
at sun.util.resources.LocaleData.getBundle(java.base@18.0.0.1-internal/LocaleData.java:182)
at sun.util.resources.LocaleData.getTimeZoneNames(java.base@18.0.0.1-internal/LocaleData.java:113)
at sun.util.locale.provider.LocaleResources.getTimeZoneNames(java.base@18.0.0.1-internal/LocaleResources.java:280)
at sun.util.locale.provider.TimeZoneNameProviderImpl.getDisplayNameArray(java.base@18.0.0.1-internal/TimeZoneNameProviderImpl.java:127)
at sun.util.cldr.CLDRTimeZoneNameProviderImpl.deriveFallbackName(java.base@18.0.0.1-internal/CLDRTimeZoneNameProviderImpl.java:157)
at sun.util.cldr.CLDRTimeZoneNameProviderImpl.deriveFallbackNames(java.base@18.0.0.1-internal/CLDRTimeZoneNameProviderImpl.java:135)
at sun.util.cldr.CLDRTimeZoneNameProviderImpl.getDisplayNameArray(java.base@18.0.0.1-internal/CLDRTimeZoneNameProviderImpl.java:111)
at sun.util.locale.provider.TimeZoneNameProviderImpl.getGenericDisplayName(java.base@18.0.0.1-internal/TimeZoneNameProviderImpl.java:113)
at sun.util.locale.provider.TimeZoneNameUtility$TimeZoneNameGetter.getName(java.base@18.0.0.1-internal/TimeZoneNameUtility.java:277)
at sun.util.locale.provider.TimeZoneNameUtility$TimeZoneNameGetter.getObject(java.base@18.0.0.1-internal/TimeZoneNameUtility.java:229)
at sun.util.locale.provider.TimeZoneNameUtility$TimeZoneNameGetter.getObject(java.base@18.0.0.1-internal/TimeZoneNameUtility.java:215)
at sun.util.locale.provider.LocaleServiceProviderPool.getLocalizedObjectImpl(java.base@18.0.0.1-internal/LocaleServiceProviderPool.java:275)
at sun.util.locale.provider.LocaleServiceProviderPool.getLocalizedObject(java.base@18.0.0.1-internal/LocaleServiceProviderPool.java:236)
at sun.util.locale.provider.TimeZoneNameUtility.retrieveDisplayNamesImpl(java.base@18.0.0.1-internal/TimeZoneNameUtility.java:197)
at sun.util.locale.provider.TimeZoneNameUtility.retrieveDisplayName(java.base@18.0.0.1-internal/TimeZoneNameUtility.java:150)
at java.util.TimeZone.getDisplayName(java.base@18.0.0.1-internal/TimeZone.java:402)
at test.java.time.format.TestZoneTextPrinterParser.test_printText(TestZoneTextPrinterParser.java:89)
at java.lang.invoke.LambdaForm$DMH/0x0000000801030800.invokeVirtual(java.base@18.0.0.1-internal/LambdaForm$DMH)
at java.lang.invoke.LambdaForm$MH/0x0000000801038000.invoke(java.base@18.0.0.1-internal/LambdaForm$MH)
at java.lang.invoke.Invokers$Holder.invokeExact_MT(java.base@18.0.0.1-internal/Invokers$Holder)
at jdk.internal.reflect.DirectMethodHandleAccessor.invokeImpl(java.base@18.0.0.1-internal/DirectMethodHandleAccessor.java:154)
at jdk.internal.reflect.DirectMethodHandleAccessor.invoke(java.base@18.0.0.1-internal/DirectMethodHandleAccessor.java:104)
at java.lang.reflect.Method.invoke(java.base@18.0.0.1-internal/Method.java:577)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:132)
at org.testng.internal.TestInvoker.invokeMethod(TestInvoker.java:599)
at org.testng.internal.TestInvoker.invokeTestMethod(TestInvoker.java:174)
at org.testng.internal.MethodRunner.runInSequence(MethodRunner.java:46)
at org.testng.internal.TestInvoker$MethodInvocationAgent.invoke(TestInvoker.java:822)
at org.testng.internal.TestInvoker.invokeTestMethods(TestInvoker.java:147)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:146)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:128)
at org.testng.TestRunner$$Lambda$84/0x000000080102e828.accept(Unknown Source)
at java.util.ArrayList.forEach(java.base@18.0.0.1-internal/ArrayList.java:1511)
at org.testng.TestRunner.privateRun(TestRunner.java:764)
at org.testng.TestRunner.run(TestRunner.java:585)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:384)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:378)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:337)
at org.testng.SuiteRunner.run(SuiteRunner.java:286)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:53)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:96)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1218)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1140)
at org.testng.TestNG.runSuites(TestNG.java:1069)
at org.testng.TestNG.run(TestNG.java:1037)
at com.sun.javatest.regtest.agent.TestNGRunner.main(TestNGRunner.java:94)
at com.sun.javatest.regtest.agent.TestNGRunner.main(TestNGRunner.java:54)
at java.lang.invoke.LambdaForm$DMH/0x0000000801002000.invokeStatic(java.base@18.0.0.1-internal/LambdaForm$DMH)
at java.lang.invoke.LambdaForm$MH/0x0000000801003400.invoke(java.base@18.0.0.1-internal/LambdaForm$MH)
at java.lang.invoke.Invokers$Holder.invokeExact_MT(java.base@18.0.0.1-internal/Invokers$Holder)
at jdk.internal.reflect.DirectMethodHandleAccessor.invokeImpl(java.base@18.0.0.1-internal/DirectMethodHandleAccessor.java:155)
at jdk.internal.reflect.DirectMethodHandleAccessor.invoke(java.base@18.0.0.1-internal/DirectMethodHandleAccessor.java:104)
at java.lang.reflect.Method.invoke(java.base@18.0.0.1-internal/Method.java:577)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
at java.lang.Thread.run(java.base@18.0.0.1-internal/Thread.java:833)

The occuring timeouts might be related to the change https://bugs.openjdk.java.net/browse/JDK-8275721 touching
src/java.base/share/classes/sun/util/cldr/CLDRTimeZoneNameProviderImpl.java , see https://github.com/openjdk/jdk/commit/543d1a8cf41d32dca161c9d8041f133a71bf0ecb .
At least after the change the timeouts occur MUCH more frequently.