The following 16 SA tests all timed out in the JDK16 CI:

serviceability/sa/TestType.java
serviceability/sa/TestSysProps.java
serviceability/sa/TestJmapCoreMetaspace.java
serviceability/sa/ClhsdbPrintAll.java
serviceability/sa/ClhsdbPmap.java#id0
serviceability/sa/ClhsdbLongConstant.java
serviceability/sa/ClhsdbJstackXcompStress.java
serviceability/sa/ClhsdbJstack.java#id1
serviceability/sa/ClhsdbJstack.java#id0
serviceability/sa/ClhsdbJhisto.java
serviceability/sa/ClhsdbJdis.java
serviceability/sa/ClhsdbInspect.java
serviceability/sa/ClhsdbFlags.java
serviceability/sa/ClhsdbFindPC.java#id2
serviceability/sa/ClhsdbFindPC.java#id0

I checked the logs for all 15 failures and I did not see anything unusual.

Here's a snippet from the TestType.java log file:

#section:main
----------messages:(6/199)----------
command: main TestType
reason: User specified action: run main/othervm TestType
Mode: othervm [/othervm specified]
Timeout information:
--- Timeout information end.
elapsed time (seconds): 1185.214
----------configuration:(0/0)----------
----------System.out:(8/1499)----------
Starting TestType test
Command line: ['/System/Volumes/Data/mesos/work_dir/jib-master/install/jdk-16+16-649/macosx-x64-debug.jdk/jdk-16/fastdebug/bin/java' '-XX:MaxRAMPercentage=4' '-Djava.io.tmpdir=/System/Volumes/Data/mesos/work_dir/slaves/4076d11c-c6ed-4d07-84c1-4ab8d55cd975-S106713/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/cbe87a76-eda9-4d79-abb8-37c29fcdc77d/runs/923b730c-2f53-46b6-afc8-01674b4acc61/testoutput/test-support/jtreg_open_test_hotspot_jtreg_serviceability_sa/tmp' '-Xshare:off' '-showversion' '-cp' '/System/Volumes/Data/mesos/work_dir/slaves/4076d11c-c6ed-4d07-84c1-4ab8d55cd975-S106713/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/cbe87a76-eda9-4d79-abb8-37c29fcdc77d/runs/923b730c-2f53-46b6-afc8-01674b4acc61/testoutput/test-support/jtreg_open_test_hotspot_jtreg_serviceability_sa/classes/5/serviceability/sa/TestType.d:/System/Volumes/Data/mesos/work_dir/slaves/4076d11c-c6ed-4d07-84c1-4ab8d55cd975-S106713/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/cbe87a76-eda9-4d79-abb8-37c29fcdc77d/runs/923b730c-2f53-46b6-afc8-01674b4acc61/testoutput/test-support/jtreg_open_test_hotspot_jtreg_serviceability_sa/classes/5/test/lib' 'jdk.test.lib.apps.LingeredApp' '8536d1c5-fbe1-479c-841d-366c6e2b088c.lck']
Started LingeredApp with pid 52267
Target JDK is not signed.
Starting clhsdb against 52267
Adding 'sudo -E -n' to the command.
[2020-09-11T19:33:52.990270Z] Gathering output for process 52271
Timeout refired 480 times
----------System.err:(3/172)----------
java version "16-ea" 2021-03-16
Java(TM) SE Runtime Environment (fastdebug build 16-ea+16-649)
Java HotSpot(TM) 64-Bit Server VM (fastdebug build 16-ea+16-649, mixed mode)
----------rerun:(36/7292)*----------