Merge pull request #1305 from shaburov/issue-772.deadlockFix

Fix #772

Author: cbeust

CHANGES.txt

@@ -1,4 +1,5 @@
 Current
+Fixed: GITHUB-772: Severe thread contention while running large test with parallel methods (Shaburov Oleg)
 Fixed: GITHUB-1298: ITestResult injection is failing in BeforeMethod method (Krishnan Mahadevan)
 Fixed: GITHUB-1293: Beanshell based execution does not work any more (Krishnan Mahadevan)
 Fixed: GITHUB-1262: Testcases out of order in XML file in junitreport folder when using testng (Krishnan Mahadevan)

src/main/java/org/testng/internal/thread/graph/GraphThreadPoolExecutor.java

@@ -9,6 +9,7 @@
 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ThreadFactory;
@@ -26,7 +27,7 @@ public class GraphThreadPoolExecutor<T> extends ThreadPoolExecutor {
   private static final boolean DOT_FILES = false;
 
   private DynamicGraph<T> m_graph;
-  private List<Runnable> m_activeRunnables = Lists.newArrayList();
+  private List<Runnable> m_activeRunnables = Collections.synchronizedList(Lists.<Runnable>newArrayList());
   private IThreadWorkerFactory<T> m_factory;
   private List<String> m_dotFiles = Lists.newArrayList();
   private int m_threadCount;