Specifically noticed on linux-aarch64, detection of port clashes by LocateRegistry.createRegistry(port) appears "racy".
Predictable port clashes can be avoided, tests that are likely to run at the same time should not choose the same port. Why now? The RMI related parts are obviously fairly stable these days, as are the tests themselves. Our OS version/host mix for testing may have changed. The problems I looked into were on ol8-aarch64. It doesn't seem necessary to add complexities to the tests, or change LocateRegistry much at this point, when a simple change to the tests can avoid asking for so many port clashes. test/jdk/javax/management/remote/mandatory/passwordAuthenticator/RMIPasswdAuthTest.java: int port = 5800; // 5801 to 5820 test/jdk/javax/management/remote/mandatory/passwordAuthenticator/RMIAltAuthTest.java: int port = 5800; // 5821 to 5840 test/jdk/javax/management/remote/mandatory/socketFactories/RMISocketFactoriesTest.java: int port = 5800; // 5841 to 5860 test/jdk/javax/management/remote/mandatory/subjectDelegation/SubjectDelegation1Test.java: int port = 5800; // 5861 to 5880 test/jdk/javax/management/remote/mandatory/subjectDelegation/SubjectDelegation2Test.java: int port = 5800; // 5881 to 5900 test/jdk/javax/management/remote/mandatory/subjectDelegation/SubjectDelegation3Test.java: int port = 5800; // 5901 to 5920 ------------- Commit messages: - update - 8313174: Create fewer predictable port clashes in management tests Changes: https://git.openjdk.org/jdk/pull/15039/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15039&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8313174 Stats: 16 lines in 6 files changed: 0 ins; 0 del; 16 mod Patch: https://git.openjdk.org/jdk/pull/15039.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/15039/head:pull/15039 PR: https://git.openjdk.org/jdk/pull/15039