HADOOP-135. Fix potential deadlock in JobTracker by acquiring locks in a consistent order. Contributed by Owen.

git-svn-id: https://svn.apache.org/repos/asf/lucene/hadoop/trunk@417249 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -44,6 +44,9 @@ Trunk (unreleased changes)
 10. HADOOP-319.  Fix FileSystem.close() to remove the FileSystem
     instance from the cache.  (Hairong Kuang via cutting)
 
+11. HADOOP-135.  Fix potential deadlock in JobTracker by acquiring
+    locks in a consistent order.  (omalley via cutting)
+
 
 Release 0.3.2 - 2006-06-09
 

src/java/org/apache/hadoop/mapred/JobTracker.java

@@ -255,8 +255,8 @@ public class JobTracker implements MRConstants, InterTrackerProtocol, JobSubmiss
                 }
                 
                 synchronized (jobs) {
-                    synchronized (jobInitQueue) {
-                        synchronized (jobsByArrival) {
+                    synchronized (jobsByArrival) {
+                        synchronized (jobInitQueue) {
                             for (Iterator it = jobs.keySet().iterator(); it.hasNext(); ) {
                                 String jobid = (String) it.next();
                                 JobInProgress job = (JobInProgress) jobs.get(jobid);