The following test timed out:

serviceability/sa/TestJmapCore.java

Here's a snippet from the log file:

----------System.out:(42/4333)----------
Command line: [/mesos/work_dir/jib-master/install/jdk-16+29-2089/macosx-x64-debug.jdk/jdk-16/fastdebug/bin/java -cp /mesos/work_dir/slaves/4076d11c-c6ed-4d07-84c1-4ab8d55cd975-S149862/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b205764e-ee1a-4ca9-9215-5fec653c9eac/runs/464ec356-619e-44bf-9247-f85dd796f8af/testoutput/test-support/jtreg_open_test_hotspot_jtreg_serviceability_sa/classes/1/serviceability/sa/TestJmapCore.d:/mesos/work_dir/jib-master/install/jdk-16+29-2089/src.full/open/test/hotspot/jtreg/serviceability/sa:/mesos/work_dir/slaves/4076d11c-c6ed-4d07-84c1-4ab8d55cd975-S149862/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b205764e-ee1a-4ca9-9215-5fec653c9eac/runs/464ec356-619e-44bf-9247-f85dd796f8af/testoutput/test-support/jtreg_open_test_hotspot_jtreg_serviceability_sa/classes/1/test/lib:/mesos/work_dir/jib-master/install/jtreg/5.1/b01/bundles/jtreg_bin-5.1.zip/jtreg/lib/javatest.jar:/mesos/work_dir/jib-master/install/jtreg/5.1/b01/bundles/jtreg_bin-5.1.zip/jtreg/lib/jtreg.jar:/mesos/work_dir/jib-master/install/jtreg/5.1/b01/bundles/jtreg_bin-5.1.zip/jtreg/lib/junit.jar:/mesos/work_dir/jib-master/install/jtreg/5.1/b01/bundles/jtreg_bin-5.1.zip/jtreg/lib/testng.jar -XX:MaxRAMPercentage=12 -Djava.io.tmpdir=/mesos/work_dir/slaves/4076d11c-c6ed-4d07-84c1-4ab8d55cd975-S149862/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b205764e-ee1a-4ca9-9215-5fec653c9eac/runs/464ec356-619e-44bf-9247-f85dd796f8af/testoutput/test-support/jtreg_open_test_hotspot_jtreg_serviceability_sa/tmp -Xshare:off -showversion -XX:+CreateCoredumpOnCrash -Xmx512m -XX:MaxMetaspaceSize=64m -XX:+CrashOnOutOfMemoryError TestJmapCore heap ]
[2020-12-16T15:03:11.613843Z] Gathering output for process 46756
[2020-12-16T15:03:12.081754Z] Waiting for completion for process 46756
[2020-12-16T15:03:12.081967Z] Waiting for completion finished for process 46756
Output and diagnostic info for process 46756 was saved into 'pid-46756-output.log'
[2020-12-16T15:03:12.377340Z] Waiting for completion for process 46756
[2020-12-16T15:03:12.378026Z] Waiting for completion finished for process 46756
Run test with ulimit -c: unlimited
[2020-12-16T15:03:12.385781Z] Gathering output for process 46758
[2020-12-16T15:14:16.790198Z] Waiting for completion for process 46758
[2020-12-16T15:14:16.802199Z] Waiting for completion finished for process 46758
Output and diagnostic info for process 46758 was saved into 'pid-46758-output.log'
crashOutputString = [Aborting due to java.lang.OutOfMemoryError: Java heap space
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc: SuppressErrorAt=/debug.cpp:343
#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/System/Volumes/Data/mesos/work_dir/slaves/983c483a-6907-44e0-ad29-98c7183575e2-S18232/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/00183101-76ba-4a20-a54c-72327865748d/runs/4bd3943f-13ee-44e6-beb2-ab2931df253f/workspace/open/src/hotspot/share/utilities/debug.cpp:343), pid=46759, tid=8195
# fatal error: OutOfMemory encountered: Java heap space
#
# JRE version: Java(TM) SE Runtime Environment (16.0+29) (fastdebug build 16-ea+29-2089)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 16-ea+29-2089, mixed mode, tiered, compressed oops, g1 gc, bsd-amd64)
# Core dump will be written. Default location: core.46759
#
# An error report file with more information is saved as:
# /mesos/work_dir/slaves/4076d11c-c6ed-4d07-84c1-4ab8d55cd975-S149862/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/b205764e-ee1a-4ca9-9215-5fec653c9eac/runs/464ec356-619e-44bf-9247-f85dd796f8af/testoutput/test-support/jtreg_open_test_hotspot_jtreg_serviceability_sa/scratch/1_1/hs_err_pid46759.log
#
# If you would like to submit a bug report, please visit:
# https://bugreport.java.com/bugreport/crash.jsp
#
]
getCoreFileLocation found stringWithLocation = core.46759
Found core file: core.46759
[2020-12-16T15:14:35.390488Z] Gathering output for process 46894
Attaching to core core.46759 from executable /mesos/work_dir/jib-master/install/jdk-16+29-2089/macosx-x64-debug.jdk/jdk-16/fastdebug/bin/java, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 16-ea+29-2089
heap written to heap.hprof

PASSED
----------System.err:(7/210)----------
java version "16-ea" 2021-03-16
Java(TM) SE Runtime Environment (fastdebug build 16-ea+29-2089)
Java HotSpot(TM) 64-Bit Server VM (fastdebug build 16-ea+29-2089, mixed mode)


JavaTest Message: Test complete.

result: Error. Agent error: java.lang.Exception: Agent 9 timed out with a timeout of 960 seconds; check console log for any additional details


Ignore the "fatal error: OutOfMemory encountered: Java heap space"
since that is a normal part of this test.

Since the test shows "PASSED" in System.out, I think the test
managed to pass while the timeout handler was running. The
test is already invoked with "run driver/timeout=240" so with a
default timeoutFactor of 4 the total timeout is 16 minutes/960
seconds.

It could be that this test machine is simply getting to be too old.