HDFS-7871. NameNodeEditLogRoller can keep printing 'Swallowing exception' message. Contributed by Jing Zhao.

(cherry picked from commit b442aeec95abfa1c6f835a116dfe6e186b0d841d)
(cherry picked from commit 6090f51725e2b44d794433ed72a1901fae2ba7e3)
(cherry picked from commit e1af1ac4e91d36b21df18ce5627e1f69f27f0776)

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -82,6 +82,9 @@ Release 2.6.1 - UNRELEASED
     HDFS-7763. fix zkfc hung issue due to not catching exception in a corner
     case. (Liang Xie via wang)
 
+    HDFS-7871. NameNodeEditLogRoller can keep printing "Swallowing exception"
+    message. (jing9)
+
 Release 2.6.0 - 2014-11-18
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -5203,14 +5203,16 @@ public class FSNamesystem implements Namesystem, FSClusterStats,
                 + rollThreshold);
             rollEditLog();
           }
+        } catch (Exception e) {
+          FSNamesystem.LOG.error("Swallowing exception in "
+              + NameNodeEditLogRoller.class.getSimpleName() + ":", e);
+        }
+        try {
           Thread.sleep(sleepIntervalMs);
         } catch (InterruptedException e) {
           FSNamesystem.LOG.info(NameNodeEditLogRoller.class.getSimpleName()
               + " was interrupted, exiting");
           break;
-        } catch (Exception e) {
-          FSNamesystem.LOG.error("Swallowing exception in "
-              + NameNodeEditLogRoller.class.getSimpleName() + ":", e);
         }
       }
     }