The following test timed out in the JDK20 CI:

serviceability/attach/AttachWithStalePidFile.java

Here's a snippet from the log file:

#section:driver
----------messages:(10/420)----------
command: driver AttachWithStalePidFile
reason: User specified action: run driver AttachWithStalePidFile
Mode: agentvm
Agent id: 15
Additional exports to unnamed modules from @modules: jdk.attach/sun.tools.attach
Additional opens to unnamed modules from @modules: java.base/jdk.internal.misc java.base/java.lang
Timeout refired 480 times
Timeout information:
--- Timeout information end.
elapsed time (seconds): 560.337
----------configuration:(19/2391)----------

<snip>

----------System.out:(1/1816)----------
Command line: [/System/Volumes/Data/mesos/work_dir/jib-master/install/jdk-20+5-232/macosx-aarch64-debug.jdk/jdk-20/fastdebug/bin/java -cp /System/Volumes/Data/mesos/work_dir/slaves/0c72054a-24ab-4dbb-944f-97f9341a1b96-S24234/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/7bbc8eec-c71f-4efd-ac6f-75b222842441/runs/d0f323b9-caef-408c-a195-1fc5067d7949/testoutput/test-support/jtreg_open_test_hotspot_jtreg_tier1_serviceability/classes/0/serviceability/attach/AttachWithStalePidFile.d:/System/Volumes/Data/mesos/work_dir/jib-master/install/jdk-20+5-232/src.full/open/test/hotspot/jtreg/serviceability/attach:/System/Volumes/Data/mesos/work_dir/slaves/0c72054a-24ab-4dbb-944f-97f9341a1b96-S24234/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/7bbc8eec-c71f-4efd-ac6f-75b222842441/runs/d0f323b9-caef-408c-a195-1fc5067d7949/testoutput/test-support/jtreg_open_test_hotspot_jtreg_tier1_serviceability/classes/0/test/lib:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/6.1/1/bundles/jtreg-6.1+1.zip/jtreg/lib/javatest.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/6.1/1/bundles/jtreg-6.1+1.zip/jtreg/lib/jtreg.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/6.1/1/bundles/jtreg-6.1+1.zip/jtreg/lib/junit.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/6.1/1/bundles/jtreg-6.1+1.zip/jtreg/lib/hamcrest.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/6.1/1/bundles/jtreg-6.1+1.zip/jtreg/lib/testng.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/6.1/1/bundles/jtreg-6.1+1.zip/jtreg/lib/jcommander.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/6.1/1/bundles/jtreg-6.1+1.zip/jtreg/lib/guice.jar -XX:+UnlockDiagnosticVMOptions -XX:+PauseAtStartup AttachWithStalePidFileTarget ]
----------System.err:(15/970)----------
java.io.IOException: Premature EOF
at jdk.attach/sun.tools.attach.HotSpotVirtualMachine.readInt(HotSpotVirtualMachine.java:344)
at jdk.attach/sun.tools.attach.VirtualMachineImpl.execute(VirtualMachineImpl.java:193)
at jdk.attach/sun.tools.attach.HotSpotVirtualMachine.executeCommand(HotSpotVirtualMachine.java:313)
at jdk.attach/sun.tools.attach.HotSpotVirtualMachine.remoteDataDump(HotSpotVirtualMachine.java:270)
at AttachWithStalePidFile.runTest(AttachWithStalePidFile.java:82)
at AttachWithStalePidFile.main(AttachWithStalePidFile.java:53)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
at java.base/java.lang.reflect.Method.invoke(Method.java:578)
at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:312)
at java.base/java.lang.Thread.run(Thread.java:1589)

JavaTest Message: Test threw exception: java.io.IOException
JavaTest Message: shutting down test

result: Error. Agent error: java.lang.Exception: Agent 15 timed out with a timeout of 480 seconds; check console log for any additional details