YARN-1575. Public localizer crashes with "Localized unkown resource". Contributed by Jason Lowe

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1561110 13f79535-47bb-0310-9956-ffa450edef68

hadoop-yarn-project/CHANGES.txt

@@ -366,6 +366,9 @@ Release 2.4.0 - UNRELEASED
     YARN-1607. TestRM relies on the scheduler assigning multiple containers in
     a single node update (Sandy Ryza)
 
+    YARN-1575. Public localizer crashes with "Localized unkown resource"
+    (jlowe)
+
 Release 2.3.0 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/localizer/ResourceLocalizationService.java

@@ -638,8 +638,8 @@ public class ResourceLocalizationService extends CompositeService
       super("Public Localizer");
       this.lfs = getLocalFileContext(conf);
       this.conf = conf;
-      this.pending =
-          new ConcurrentHashMap<Future<Path>, LocalizerResourceRequestEvent>();
+      this.pending = Collections.synchronizedMap(
+          new HashMap<Future<Path>, LocalizerResourceRequestEvent>());
       this.threadPool = createLocalizerExecutor(conf);
       this.queue = new ExecutorCompletionService<Path>(threadPool);
     }
@@ -675,8 +675,12 @@ public class ResourceLocalizationService extends CompositeService
             publicDirDestPath =
                 new Path(publicDirDestPath, Long.toString(publicRsrc
                   .nextUniqueNumber()));
-            pending.put(queue.submit(new FSDownload(lfs, null, conf,
-              publicDirDestPath, resource)), request);
+            // explicitly synchronize pending here to avoid future task
+            // completing and being dequeued before pending updated
+            synchronized (pending) {
+              pending.put(queue.submit(new FSDownload(lfs, null, conf,
+                  publicDirDestPath, resource)), request);
+            }
           } catch (IOException e) {
             rsrc.unlock();
             // TODO Need to Fix IO Exceptions - Notifying resource