In jtreg test java/lang/ProcessHandle/PermissionTest.java on macOS we ran a few times into this error :

java.lang.RuntimeException: Cannot allocate memory
       at java.base/java.lang.ProcessHandleImpl.getProcessPids0(Native Method)
       at java.base/java.lang.ProcessHandleImpl.children(ProcessHandleImpl.java:456)
       at java.base/java.lang.ProcessHandleImpl.children(ProcessHandleImpl.java:434)
       at PermissionTest.childrenWithPermission(PermissionTest.java:84)
       at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
       at java.base/java.lang.reflect.Method.invoke(Method.java:573)
       at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:132)
       at org.testng.internal.TestInvoker.invokeMethod(TestInvoker.java:599)
       at org.testng.internal.TestInvoker.invokeTestMethod(TestInvoker.java:174)
       at org.testng.internal.MethodRunner.runInSequence(MethodRunner.java:46)
       at org.testng.internal.TestInvoker$MethodInvocationAgent.invoke(TestInvoker.java:822)
       at org.testng.internal.TestInvoker.invokeTestMethods(TestInvoker.java:147)
       at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:146)
       at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:128)
       at java.base/java.util.ArrayList.forEach(ArrayList.java:1597)


Probably sysctl fails here, but it is not fully clear; it would help to change the exception so that the standard text is shown too.
Also in case of ENOMEM, we can retry the failing sysctl call a few times.