vm testbase LoadUnloadGC fails with OOM: metaspace

Test: vmTestbase/gc/gctests/LoadUnloadGC/LoadUnloadGC.java
Failure type: java.lang.OutOfMemoryError: Metaspace
Intermittent: yes (~2/100)
Platform: Linux-x64 (so far only seen on Linux-x64)

================= Details:
Failures summary:
java.lang.OutOfMemoryError: Metaspace
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1017)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:878)
at nsk.share.classload.ClassPathNonDelegatingClassLoader.loadClassFromFile(ClassPathNonDelegatingClassLoader.java:72)
at nsk.share.classload.ClassPathNonDelegatingClassLoader.loadClass(ClassPathNonDelegatingClassLoader.java:53)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
at nsk.share.gc.Class400.<init>(ClassChain.java:2034)
at nsk.share.gc.Class399.<init>(ClassChain.java:2029)
at nsk.share.gc.Class398.<init>(ClassChain.java:2024)
at nsk.share.gc.Class397.<init>(ClassChain.java:2019)
at nsk.share.gc.Class396.<init>(ClassChain.java:2014)
... (more)

----------System.err:(17/1093)----------
Java HotSpot(TM) 64-Bit Server VM warning: Setting CompressedClassSpaceSize has no effect when compressed class pointers are not used
nsk.share.TestFailure: Test exit code: 97
at nsk.share.test.Tests$TestRunner.execute(Tests.java:90)
at nsk.share.test.Tests$TestRunner.run(Tests.java:96)
at nsk.share.gc.GC.runTest(GC.java:114)
at gc.gctests.LoadUnloadGC.LoadUnloadGC.main(LoadUnloadGC.java:129)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
at java.base/java.lang.Thread.run(Thread.java:830)