Thank you for looking at this issue Chris Y. I don’t disagree with the changes, but if you want to confirm your suspicion, that the same port is being reused, then printing out the client’s bound port would do that ( since the servers port is already printed in the logs ).
If such a change was integrated, then the next observed failure would confirm or disconfirm your suspicion. -Chris H. > On 20 Sep 2018, at 11:50, Chris Yin <xu.y....@oracle.com> wrote: > > Loop net-dev since the test is under java/net, thanks > >> On 20 Sep 2018, at 5:30 PM, Chris Yin <xu.y....@oracle.com> wrote: >> >> Please review below minor change for 8199931, thanks >> >> A little explanation about the change here, since the failure samples are >> too less (seems too hard to repro), so below scenario which caused the >> failure is a guess. MultcastSocket constructor set reuse address true by >> default, when call “new MulticastSocket(0)” to create client socket that >> maybe in a little possibility it used same address with server, that will >> explain why the failure looks like client received data package from itself. >> Follow the guessing, I modified test code to explicit create client socket >> use same port with server, then got same failure error as reported bug on >> OEL7. Though I cannot make sure the guess is 100% match with the original >> failure, but at least we could try to prevent such possible scenario. >> >> bug: https://bugs.openjdk.java.net/browse/JDK-8199931 >> >> changes: >> >> diff -r 43668e3cae4d >> test/jdk/java/net/MulticastSocket/UnreferencedMulticastSockets.java >> --- a/test/jdk/java/net/MulticastSocket/UnreferencedMulticastSockets.java >> Thu Sep 20 08:59:03 2018 +0200 >> +++ b/test/jdk/java/net/MulticastSocket/UnreferencedMulticastSockets.java >> Thu Sep 20 16:37:36 2018 +0800 >> @@ -40,6 +40,7 @@ >> import java.net.DatagramSocket; >> import java.net.DatagramSocketImpl; >> import java.net.InetAddress; >> +import java.net.InetSocketAddress; >> import java.net.MulticastSocket; >> import java.net.UnknownHostException; >> import java.nio.file.Files; >> @@ -119,7 +120,10 @@ >> Thread thr = new Thread(svr); >> thr.start(); >> >> - MulticastSocket client = new MulticastSocket(0); >> + MulticastSocket client = new MulticastSocket(null); >> + // prevent MulticastSocket reuse previous address, see 8199931 >> + client.setReuseAddress(false); >> + client.bind(new InetSocketAddress(0)); >> client.connect(svr.getHost(), svr.getPort()); >> pendingSockets.add(new NamedWeak(client, pendingQueue, >> "clientMulticastSocket")); >> extractRefs(client, "clientMulticastSocket”); >> >> Regards, >> Chris >
