ZGC can return metaspace OOM prematurely

The following test failed in the JDK17 CI:

vmTestbase/gc/gctests/LoadUnloadGC/LoadUnloadGC.java

Here's a snippet from the log file:

#section:main
----------messages:(4/364)----------
command: main -XX:MaxMetaspaceSize=64M -XX:MetaspaceSize=32M -XX:CompressedClassSpaceSize=32M gc.gctests.LoadUnloadGC.LoadUnloadGC
reason: User specified action: run main/othervm -XX:MaxMetaspaceSize=64M -XX:MetaspaceSize=32M -XX:CompressedClassSpaceSize=32M gc.gctests.LoadUnloadGC.LoadUnloadGC
Mode: othervm [/othervm specified]
elapsed time (seconds): 369.236
----------configuration:(0/0)----------
----------System.out:(151/8218)----------
Stress time: 120 seconds
Stress iterations factor: 1
Stress threads factor: 1
Stress runs factor: 1
Max memory: 1988100096
Sleep time: 500
Iterations: 0
Number of threads: 3
Run GC thread: false
Run mem diag thread: false
Run forever: false
Starting Thread[gc.gctests.LoadUnloadGC.LoadUnloadGC$Loader@cadcfa2,5,MainThreadGroup]
Starting Thread[gc.gctests.LoadUnloadGC.LoadUnloadGC$Loader@a34b66d,5,MainThreadGroup]
Starting Thread[gc.gctests.LoadUnloadGC.LoadUnloadGC$Loader@6806b856,5,MainThreadGroup]
Exception in
Exception in
gc.gctests.LoadUnloadGC.LoadUnloadGC$Loader@cadcfa2
gc.gctests.LoadUnloadGC.LoadUnloadGC$Loader@6806b856
java.lang.OutOfMemoryError: Metaspace
at nsk.share.gc.Class451.<init>(ClassChain.java:2289)
at nsk.share.gc.Class450.<init>(ClassChain.java:2284)
at nsk.share.gc.Class449.<init>(ClassChain.java:2279)
at nsk.share.gc.Class448.<init>(ClassChain.java:2274)
at nsk.share.gc.Class447.<init>(ClassChain.java:2269)
at nsk.share.gc.Class446.<init>(ClassChain.java:2264)
at nsk.share.gc.Class445.<init>(ClassChain.java:2259)
at nsk.share.gc.Class444.<init>(ClassChain.java:2254)
at nsk.share.gc.Class443.<init>(ClassChain.java:2249)
at nsk.share.gc.Class442.<init>(ClassChain.java:2244)
at nsk.share.gc.Class441.<init>(ClassChain.java:2239)
at nsk.share.gc.Class440.<init>(ClassChain.java:2234)
at nsk.share.gc.Class439.<init>(ClassChain.java:2229)
at nsk.share.gc.Class438.<init>(ClassChain.java:2224)
at nsk.share.gc.Class437.<init>(ClassChain.java:2219)
at nsk.share.gc.Class436.<init>(ClassChain.java:2214)
at nsk.share.gc.Class435.<init>(ClassChain.java:2209)
at nsk.share.gc.Class434.<init>(ClassChain.java:2204)
at nsk.share.gc.Class433.<init>(ClassChain.java:2199)
at nsk.share.gc.Class432.<init>(ClassChain.java:2194)
at nsk.share.gc.Class431.<init>(ClassChain.java:2189)
at nsk.share.gc.Class430.<init>(ClassChain.java:2184)
at nsk.share.gc.Class429.<init>(ClassChain.java:2179)
at nsk.share.gc.Class428.<init>(ClassChain.java:2174)
at nsk.share.gc.Class427.<init>(ClassChain.java:2169)
at nsk.share.gc.Class426.<init>(ClassChain.java:2164)
at nsk.share.gc.Class425.<init>(ClassChain.java:2159)
at nsk.share.gc.Class424.<init>(ClassChain.java:2154)
at nsk.share.gc.Class423.<init>(ClassChain.java:2149)
at nsk.share.gc.Class422.<init>(ClassChain.java:2144)
at nsk.share.gc.Class421.<init>(ClassChain.java:2139)
at nsk.share.gc.Class420.<init>(ClassChain.java:2134)
java.lang.OutOfMemoryError: Compressed class space
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1010)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:872)
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:519)
at nsk.share.gc.Class778.<init>(ClassChain.java:3924)
at nsk.share.gc.Class777.<init>(ClassChain.java:3919)
at nsk.share.gc.Class776.<init>(ClassChain.java:3914)
at nsk.share.gc.Class775.<init>(ClassChain.java:3909)
at nsk.share.gc.Class774.<init>(ClassChain.java:3904)
at nsk.share.gc.Class773.<init>(ClassChain.java:3899)
at nsk.share.gc.Class772.<init>(ClassChain.java:3894)
at nsk.share.gc.Class771.<init>(ClassChain.java:3889)
at nsk.share.gc.Class770.<init>(ClassChain.java:3884)
at nsk.share.gc.Class769.<init>(ClassChain.java:3879)
at nsk.share.gc.Class768.<init>(ClassChain.java:3874)
at nsk.share.gc.Class767.<init>(ClassChain.java:3869)
at nsk.share.gc.Class766.<init>(ClassChain.java:3864)
at nsk.share.gc.Class765.<init>(ClassChain.java:3859)
at nsk.share.gc.Class764.<init>(ClassChain.java:3854)
at nsk.share.gc.Class763.<init>(ClassChain.java:3849)
at nsk.share.gc.Class762.<init>(ClassChain.java:3844)
at nsk.share.gc.Class761.<init>(ClassChain.java:3839)
at nsk.share.gc.Class760.<init>(ClassChain.java:3834)
at nsk.share.gc.Class759.<init>(ClassChain.java:3829)
at nsk.share.gc.Class758.<init>(ClassChain.java:3824)
at nsk.share.gc.Class757.<init>(ClassChain.java:3819)
at nsk.share.gc.Class756.<init>(ClassChain.java:3814)
at nsk.share.gc.Class755.<init>(ClassChain.java:3809)
at nsk.share.gc.Class754.<init>(ClassChain.java:3804)
at nsk.share.gc.Class753.<init>(ClassChain.java:3799)
Failures summary:
java.lang.OutOfMemoryError: Metaspace
at nsk.share.gc.Class451.<init>(ClassChain.java:2289)
at nsk.share.gc.Class450.<init>(ClassChain.java:2284)
at nsk.share.gc.Class449.<init>(ClassChain.java:2279)
at nsk.share.gc.Class448.<init>(ClassChain.java:2274)
at nsk.share.gc.Class447.<init>(ClassChain.java:2269)
at nsk.share.gc.Class446.<init>(ClassChain.java:2264)
at nsk.share.gc.Class445.<init>(ClassChain.java:2259)
at nsk.share.gc.Class444.<init>(ClassChain.java:2254)
at nsk.share.gc.Class443.<init>(ClassChain.java:2249)
at nsk.share.gc.Class442.<init>(ClassChain.java:2244)
at nsk.share.gc.Class441.<init>(ClassChain.java:2239)
at nsk.share.gc.Class440.<init>(ClassChain.java:2234)
at nsk.share.gc.Class439.<init>(ClassChain.java:2229)
at nsk.share.gc.Class438.<init>(ClassChain.java:2224)
at nsk.share.gc.Class437.<init>(ClassChain.java:2219)
at nsk.share.gc.Class436.<init>(ClassChain.java:2214)
at nsk.share.gc.Class435.<init>(ClassChain.java:2209)
at nsk.share.gc.Class434.<init>(ClassChain.java:2204)
at nsk.share.gc.Class433.<init>(ClassChain.java:2199)
at nsk.share.gc.Class432.<init>(ClassChain.java:2194)
at nsk.share.gc.Class431.<init>(ClassChain.java:2189)
at nsk.share.gc.Class430.<init>(ClassChain.java:2184)
at nsk.share.gc.Class429.<init>(ClassChain.java:2179)
at nsk.share.gc.Class428.<init>(ClassChain.java:2174)
at nsk.share.gc.Class427.<init>(ClassChain.java:2169)
at nsk.share.gc.Class426.<init>(ClassChain.java:2164)
at nsk.share.gc.Class425.<init>(ClassChain.java:2159)
at nsk.share.gc.Class424.<init>(ClassChain.java:2154)
at nsk.share.gc.Class423.<init>(ClassChain.java:2149)
at nsk.share.gc.Class422.<init>(ClassChain.java:2144)
at nsk.share.gc.Class421.<init>(ClassChain.java:2139)
at nsk.share.gc.Class420.<init>(ClassChain.java:2134)
java.lang.OutOfMemoryError: Compressed class space
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1010)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:872)
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:519)
at nsk.share.gc.Class778.<init>(ClassChain.java:3924)
at nsk.share.gc.Class777.<init>(ClassChain.java:3919)
at nsk.share.gc.Class776.<init>(ClassChain.java:3914)
at nsk.share.gc.Class775.<init>(ClassChain.java:3909)
at nsk.share.gc.Class774.<init>(ClassChain.java:3904)
at nsk.share.gc.Class773.<init>(ClassChain.java:3899)
at nsk.share.gc.Class772.<init>(ClassChain.java:3894)
at nsk.share.gc.Class771.<init>(ClassChain.java:3889)
at nsk.share.gc.Class770.<init>(ClassChain.java:3884)
at nsk.share.gc.Class769.<init>(ClassChain.java:3879)
at nsk.share.gc.Class768.<init>(ClassChain.java:3874)
at nsk.share.gc.Class767.<init>(ClassChain.java:3869)
at nsk.share.gc.Class766.<init>(ClassChain.java:3864)
at nsk.share.gc.Class765.<init>(ClassChain.java:3859)
at nsk.share.gc.Class764.<init>(ClassChain.java:3854)
at nsk.share.gc.Class763.<init>(ClassChain.java:3849)
at nsk.share.gc.Class762.<init>(ClassChain.java:3844)
at nsk.share.gc.Class761.<init>(ClassChain.java:3839)
at nsk.share.gc.Class760.<init>(ClassChain.java:3834)
at nsk.share.gc.Class759.<init>(ClassChain.java:3829)
at nsk.share.gc.Class758.<init>(ClassChain.java:3824)
at nsk.share.gc.Class757.<init>(ClassChain.java:3819)
at nsk.share.gc.Class756.<init>(ClassChain.java:3814)
at nsk.share.gc.Class755.<init>(ClassChain.java:3809)
at nsk.share.gc.Class754.<init>(ClassChain.java:3804)
at nsk.share.gc.Class753.<init>(ClassChain.java:3799)
----------System.err:(16/959)----------
nsk.share.TestFailure: Test exit code: 97
at nsk.share.test.Tests$TestRunner.execute(Tests.java:90)
at nsk.share.test.Tests$TestRunner.run(Tests.java:96)
at nsk.share.gc.GC.runTest(GC.java:114)
at gc.gctests.LoadUnloadGC.LoadUnloadGC.main(LoadUnloadGC.java:128)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
at java.base/java.lang.Thread.run(Thread.java:831)

JavaTest Message: Test threw exception: nsk.share.TestFailure: Test exit code: 97
JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: nsk.share.TestFailure: Test exit code: 97
----------rerun:(39/8355)*----------

The test task has the following VM args:

-XX:+CreateCoredumpOnCrash -XX:+UseZGC