vmTestbase/metaspace/stressDictionary/StressDictionary.java timed out

The following test timed out in the JDK16 CI:

vmTestbase/metaspace/stressDictionary/StressDictionary.java

Here's a snippet from the log file:

#section:main
----------messages:(6/311)----------
command: main metaspace.stressDictionary.StressDictionary -stressTime 30
reason: User specified action: run main/othervm/timeout=420 metaspace.stressDictionary.StressDictionary -stressTime 30
Mode: othervm [/othervm specified]
Timeout information:
--- Timeout information end.
elapsed time (seconds): 1755.792
----------configuration:(0/0)----------
----------System.out:(14/436)----------
Stress time: 30 seconds
Stress iterations factor: 1
Stress threads factor: 1
Stress runs factor: 1
Max memory: 1988100096
Sleep time: 500
Iterations: 0
Number of threads: 16
Run GC thread: false
Run mem diag thread: false
Run forever: false
For random generator using seed: -8136885020435654947
To re-run test with same seed value please add "-Djdk.test.lib.random.seed=-8136885020435654947" to command line.
Timeout refired 1680 times
----------System.err:(7/274)----------
java version "16-ea" 2021-03-16
Java(TM) SE Runtime Environment (fastdebug build 16-ea+27-1808)
Java HotSpot(TM) 64-Bit Server VM (fastdebug build 16-ea+27-1808, mixed mode)
INFO: There are 20 results.
INFO: no tasks were cancelled.
INFO: all tasks are done.
STATUS:Passed.
----------rerun:(36/8435)*----------

The test is configured with a timeout value of 420 and with a
default timeoutFactor of 4, the total timeout value is 1680 seconds.
The test ran for:

> elapsed time (seconds): 1755.792

and the test passed while the timeout handler was running:

> STATUS:Passed.