Re: Garbage collection race condition before final checks

[Rémi Forax]

On 11/15/2011 01:26 PM, Gary Adams wrote:

 Added PlatformLoggingMXBeanTest to the 7067691 bug fix,
e.g. instance variables for Logger variables to prevent premature
weak reference collection.

  http://cr.openjdk.java.net/~gadams/7067691/

Hi Garry,

Fresh webrevs for the other work in progress bug fixes.

  http://cr.openjdk.java.net/~gadams/6731620/

You can declare and initialize elapsed at the same place :
  final long elapsed = System.currentTimeMillis() - start;
otherwise, it looks ok.

  http://cr.openjdk.java.net/~gadams/6818464/

if you want to have a variable changed in an inner class, the usual idiom
is to use an array of one element.

     public static void main (String[] args) throws Exception  {
+        final Thread[] tdThread = new Thread[1];
         Timer t = new Timer();

         // Start a mean event that kills the timer thread
         t.schedule(new TimerTask() {
             public void run() {
+                tdThread[0] = Thread.currentThread();
                 throw new ThreadDeath();
             }
         }, 0);

         // Wait for mean event to do the deed and thread to die.
         try {
+            do {
             Thread.sleep(100);
+            } while(tdThread[0] == null);
         } catch(InterruptedException e) {
         }
+        tdThread[0].join();

         // Try to start another event
         try {
             // Timer thread is dead now
             t.schedule(new TimerTask() {

  http://cr.openjdk.java.net/~gadams/6860309/

This one is ok for me :)

  http://cr.openjdk.java.net/~gadams/7084033/

Thumb up for this one too !

cheers,
Rémi

On 11/10/11 09:41 AM, Gary Adams wrote:

 On 11/ 8/11 11:13 PM, Mandy Chung wrote:

Thanks for picking up this bug and fixing this intermittent issue. PlatformLoggingMXBeanTest.java in the same directory has the same issue. It'd be good to fix that with the same CR. These tests were copied from test/java/util/logging/LoggingMXBeanTest.java. I haven't looked in details but I wonder why the test/java/util/logging tests don't have this intermittent issue and I suspect it holds a strong reference.

I attempted to break PlatformLoggingMXBeanTest.java with a generous application of GC calls, but I could not get it to fail in the same manner as the other test. It may be

failing due to a different condition.