The following test failed in the JDK26 CI:

jdk/test/lib/hprof/HprofTest.java

Here's a snippet from the log file:

#section:main
----------messages:(8/237)----------
command: main HprofTest
reason: User specified action: run main HprofTest
started: Fri Oct 17 16:41:23.073 UTC 2025
Mode: agentvm
Agent id: 7
Process id: 2502700
finished: Fri Oct 17 16:41:49.171 UTC 2025
elapsed time (seconds): 26.098
----------configuration:(14/1845)----------

<snip>

----------System.out:(9/1865)----------
Command line: ['/opt/mach5/mesos/work_dir/jib-master/install/jdk-26+21-2091/linux-x64-open.jdk/jdk-26/bin/java' '-Xmx768m' '-XX:MaxRAMPercentage=4.16667' '-Dtest.boot.jdk=/opt/mach5/mesos/work_dir/jib-master/install/jdk/25/37/bundles/linux-x64/jdk-25_linux-x64_bin.tar.gz/jdk-25' '-Djava.io.tmpdir=/opt/mach5/mesos/work_dir/slaves/9a8d6c29-9c09-4644-b4fc-a39135134048-S11387/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b8826ca9-6512-488d-89f2-dc289e6e0ccc/runs/5bee9b58-4940-4aac-af4a-bb2f24cd9f9d/testoutput/test-support/jtreg_open_test_lib_test/tmp' '-ea' '-esa' '-cp' '/opt/mach5/mesos/work_dir/slaves/9a8d6c29-9c09-4644-b4fc-a39135134048-S11387/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b8826ca9-6512-488d-89f2-dc289e6e0ccc/runs/5bee9b58-4940-4aac-af4a-bb2f24cd9f9d/testoutput/test-support/jtreg_open_test_lib_test/classes/0/jdk/test/lib/hprof/HprofTest.d:/opt/mach5/mesos/work_dir/slaves/9a8d6c29-9c09-4644-b4fc-a39135134048-S11387/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b8826ca9-6512-488d-89f2-dc289e6e0ccc/runs/5bee9b58-4940-4aac-af4a-bb2f24cd9f9d/testoutput/test-support/jtreg_open_test_lib_test/classes/0/jdk/test/lib/hprof/HprofTest.d/test/lib' 'HprofTestTarg' 'ac07f703-2ac9-4bd9-adcd-41492ac8f44e.lck']
LingeredApp startup took 1030ms
Check for hs_err_pid/core/mdmp files:
None.
[jcmd]:/opt/mach5/mesos/work_dir/jib-master/install/jdk-26+21-2091/linux-x64-open.jdk/jdk-26/bin/jcmd 2503034 GC.heap_dump /opt/mach5/mesos/work_dir/slaves/9a8d6c29-9c09-4644-b4fc-a39135134048-S11387/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b8826ca9-6512-488d-89f2-dc289e6e0ccc/runs/5bee9b58-4940-4aac-af4a-bb2f24cd9f9d/testoutput/test-support/jtreg_open_test_lib_test/scratch/1/Myheapdump.hprof
[jcmd] 2503034:
 LingeredApp stdout: [];
 LingeredApp stderr: []
 LingeredApp exitValue = 0
----------System.err:(17/1177)----------
[jcmd] com.sun.tools.attach.AttachNotSupportedException: Unable to open socket file /proc/2503034/root/tmp/.java_pid2503034: target process 2503034 doesn't respond within 10500ms or HotSpot VM not loaded
[jcmd] at jdk.attach/sun.tools.attach.VirtualMachineImpl.<init>(VirtualMachineImpl.java:115)
[jcmd] at jdk.attach/sun.tools.attach.AttachProviderImpl.attachVirtualMachine(AttachProviderImpl.java:56)
[jcmd] at jdk.attach/com.sun.tools.attach.VirtualMachine.attach(VirtualMachine.java:201)
[jcmd] at jdk.jcmd/sun.tools.jcmd.JCmd.executeCommandForPid(JCmd.java:113)
[jcmd] at jdk.jcmd/sun.tools.jcmd.JCmd.main(JCmd.java:97)
java.lang.Exception: Jcmd exited with code 1
at HprofTest.createDump(HprofTest.java:97)
at HprofTest.main(HprofTest.java:70)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
at java.base/java.lang.reflect.Method.invoke(Method.java:565)
at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:335)
at java.base/java.lang.Thread.run(Thread.java:1474)

JavaTest Message: Test threw exception: java.lang.Exception
JavaTest Message: shutting down test

result: Failed. Execution failed: `main' threw exception: java.lang.Exception: Jcmd exited with code 1

Normally a Tier1 test failure would start out as a P2, but this failure
did not reproduce in at least the next six build-IDs so I'm also tagging
it as intermittent.