Re: svn commit: r1454793 - /river/jtsk/skunk/qa_refactor/trunk/src/com/sun/jini/jeri/internal/mux/Mux.java

[Peter Firmstone <ji...@zeus.net.au>]

Note; this test is capable of fully saturating 4 CPU's to 100%.

peter_firmstone@apache.org wrote:
> Author: peter_firmstone
> Date: Sun Mar 10 06:04:40 2013
> New Revision: 1454793
>
> URL: http://svn.apache.org/r1454793
> Log:
> Mux field defaultTimout was written by threads synchronizing on ConnectionManager's lock during startup, however reads were performed while holding muxLock.  The documentation stated that access to defaultTimeout was unsynchronized.
>
> The failing test:
> com/sun/jini/test/impl/outrigger/matching/StressTestWithShutdown.td
>  
> Suspected cause: because reads and writes were synchronized on different locks and defaultTimout was neither final nor volatile, threads could see defaultTimeout in it's default constructed state of 0, causing an IOException: 
>
>      [java] TestBase.fail FINE: WriteTask_190: Caught an unexpected Exception during a retry
>      [java] java.rmi.ConnectIOException: I/O exception connecting to BasicObjectEndpoint[b3755737-cdf3-49d7-adb1-33197bc3a993,TcpEndpoint[10.1.1.2:54176]]; nested exception is:
>      [java]     java.io.IOException: timeout waiting for server to respond to handshake
>      [java]     at net.jini.jeri.BasicInvocationHandler.wrapSafeIOException(BasicInvocationHandler.java:893)
>      [java]     at net.jini.jeri.BasicInvocationHandler.invokeRemoteMethodOnce(BasicInvocationHandler.java:711)
>      [java]     at net.jini.jeri.BasicInvocationHandler.invokeRemoteMethod(BasicInvocationHandler.java:659)
>      [java]     at net.jini.jeri.BasicInvocationHandler.invoke(BasicInvocationHandler.java:528)
>      [java]     at com.sun.jini.outrigger.$Proxy1.write(Unknown Source)
>      [java]     at com.sun.jini.outrigger.SpaceProxy2.write(SpaceProxy2.java:296)
>      [java]     at com.sun.jini.test.impl.outrigger.matching.StressTest$WriteRandomEntryTask.spaceWrite(StressTest.java:585)
>      [java]     at com.sun.jini.test.impl.outrigger.matching.StressTest$WriteRandomEntryTask.run(StressTest.java:548)
>      [java]     at com.sun.jini.thread.TaskManager$TaskThread.run(TaskManager.java:331)
>      [java] Caused by: java.io.IOException: timeout waiting for server to respond to handshake
>      [java]     at com.sun.jini.jeri.internal.mux.MuxClient.newRequest(MuxClient.java:68)
>      [java]     at net.jini.jeri.connection.ConnectionManager$OutboundMux.newRequest(ConnectionManager.java:391)
>      [java]     at net.jini.jeri.connection.ConnectionManager$ReqIterator.next(ConnectionManager.java:665)
>      [java]     at net.jini.jeri.BasicObjectEndpoint$1.next(BasicObjectEndpoint.java:370)
>      [java]     at net.jini.jeri.BasicInvocationHandler.invokeRemoteMethodOnce(BasicInvocationHandler.java:708)
>      [java]     ... 7 more
>
> I was reliably able to reproduce this on Solaris 10 sparc, 4 x 450MHz Ultra 80 with interleaved Ram.
>
> java version "1.6.0_30"
> Java(TM) SE Runtime Environment (build 1.6.0_30-b12)
> Java HotSpot(TM) Server VM (build 20.5-b03, mixed mode)
>
> Changing the field to volatile (state wasn't dependant on previous state and wouldn't cause deadlock) fixed the issue.
>
> Modified:
>     river/jtsk/skunk/qa_refactor/trunk/src/com/sun/jini/jeri/internal/mux/Mux.java
>
> Modified: river/jtsk/skunk/qa_refactor/trunk/src/com/sun/jini/jeri/internal/mux/Mux.java
> URL: http://svn.apache.org/viewvc/river/jtsk/skunk/qa_refactor/trunk/src/com/sun/jini/jeri/internal/mux/Mux.java?rev=1454793&r1=1454792&r2=1454793&view=diff
> ==============================================================================
> --- river/jtsk/skunk/qa_refactor/trunk/src/com/sun/jini/jeri/internal/mux/Mux.java (original)
> +++ river/jtsk/skunk/qa_refactor/trunk/src/com/sun/jini/jeri/internal/mux/Mux.java Sun Mar 10 06:04:40 2013
> @@ -137,7 +137,9 @@ abstract class Mux {
>      final Map sessions = new HashMap(5);
>  
>      private int expectedPingCookie = -1;
> -    private long startTimeout = 15000; // milliseconds
> +    
> +    /** unguarded instance state */
> +    private volatile long startTimeout = 15000; // milliseconds
>  
>      /**
>       * Constructs a new Mux instance for a connection accessible through
>
>
>
>