HDFS-2360. Ugly stacktrce when quota exceeds. (harsh)

(cherry picked from commit 046521cd6511b7fc6d9478cb2bed90d8e75fca20)

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

@@ -8,6 +8,8 @@ Release 2.8.0 - UNRELEASED
 
   IMPROVEMENTS
 
+    HDFS-2360. Ugly stacktrace when quota exceeds. (harsh)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSOutputStream.java

@@ -57,6 +57,7 @@ import org.apache.hadoop.fs.Syncable;
 import org.apache.hadoop.hdfs.client.HdfsDataOutputStream;
 import org.apache.hadoop.hdfs.client.HdfsDataOutputStream.SyncFlag;
 import org.apache.hadoop.hdfs.protocol.BlockStoragePolicy;
+import org.apache.hadoop.hdfs.protocol.QuotaExceededException;
 import org.apache.hadoop.hdfs.protocol.DSQuotaExceededException;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -550,7 +551,13 @@ public class DFSOutputStream extends FSOutputSummer
         } catch (Throwable e) {
           // Log warning if there was a real error.
           if (restartingNodeIndex.get() == -1) {
-            DFSClient.LOG.warn("DataStreamer Exception", e);
+            // Since their messages are descriptive enough, do not always
+            // log a verbose stack-trace WARN for quota exceptions.
+            if (e instanceof QuotaExceededException) {
+              DFSClient.LOG.debug("DataStreamer Quota Exception", e);
+            } else {
+              DFSClient.LOG.warn("DataStreamer Exception", e);
+            }
           }
           if (e instanceof IOException) {
             setLastException((IOException)e);