The test failed because the cache usage was larger by 256 bytes. The test was run with '-XX:-SegmentedCodeCache' and UsageTracker, on Mac OSX 13, aarch64-debug.

The log snippet and stack trace:

java.lang.RuntimeException: free shouldn't increase memory usage: 1888640 <= 1888384: expected that 1888640 <= 1888384
at jdk.test.lib.Asserts.fail(Asserts.java:594)
at jdk.test.lib.Asserts.assertLessThanOrEqual(Asserts.java:154)
at jdk.test.lib.Asserts.assertLTE(Asserts.java:125)
at compiler.whitebox.AllocationCodeBlobTest.test(AllocationCodeBlobTest.java:119)
at compiler.whitebox.AllocationCodeBlobTest.main(AllocationCodeBlobTest.java:71)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
at java.base/java.lang.reflect.Method.invoke(Method.java:580)
at com.sun.javatest.regtest.agent.MainWrapper$MainTask.run(MainWrapper.java:138)
at java.base/java.lang.Thread.run(Thread.java:1583)

An unlucky race condition? Or a repetition of the JDK-8148751?