MAPREDUCE-2187. Reporter sends progress during sort/merge. Contributed by Anupam Seth.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20-security@1152944 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -180,6 +180,9 @@ Release 0.20.204.0 - unreleased
 
   IMPROVEMENTS
 
+    MAPREDUCE-2187. Reporter sends progress during sort/merge. (Anupam Seth via
+    acmurthy) 
+
     HADOOP-7144. Expose JMX metrics via JSON servlet. (Robert Joseph Evans via
     cdouglas)
 

src/mapred/mapred-default.xml

@@ -1131,6 +1131,14 @@
   </description>
 </property>
 
+<property>
+  <name>mapred.combine.recordsBeforeProgress</name>
+  <value>10000</value>
+  <description> The number of records to process during combine output collection
+   before sending a progress notification to the TaskTracker.
+  </description>
+</property>
+
 <property>
   <name>mapred.merge.recordsBeforeProgress</name>
   <value>10000</value>

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

@@ -982,7 +982,7 @@ class MapTask extends Task {
                                              combineInputCounter,
                                              reporter, null);
       if (combinerRunner != null) {
-        combineCollector= new CombineOutputCollector<K,V>(combineOutputCounter);
+        combineCollector= new CombineOutputCollector<K,V>(combineOutputCounter, reporter, conf);
       } else {
         combineCollector = null;
       }

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

@@ -1928,7 +1928,7 @@ class ReduceTask extends Task {
                                                   reporter, null);
       if (combinerRunner != null) {
         combineCollector = 
-          new CombineOutputCollector(reduceCombineOutputCounter);
+          new CombineOutputCollector(reduceCombineOutputCounter, reporter, conf);
       }
       
       this.ioSortFactor = conf.getInt("io.sort.factor", 10);

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

@@ -65,6 +65,8 @@ import org.apache.hadoop.fs.FSDataInputStream;
 abstract public class Task implements Writable, Configurable {
   private static final Log LOG =
     LogFactory.getLog(Task.class);
+  public static final String MR_COMBINE_RECORDS_BEFORE_PROGRESS = "mapred.combine.recordsBeforeProgress";
+  public static final long DEFAULT_MR_COMBINE_RECORDS_BEFORE_PROGRESS = 10000;
 
   // Counters used by Task subclasses
   public static enum Counter { 
@@ -1083,16 +1085,26 @@ abstract public class Task implements Writable, Configurable {
   implements OutputCollector<K, V> {
     private Writer<K, V> writer;
     private Counters.Counter outCounter;
-    public CombineOutputCollector(Counters.Counter outCounter) {
+    private Progressable progressable;
+    private long progressBar;
+
+    public CombineOutputCollector(Counters.Counter outCounter, Progressable progressable, Configuration conf) {
       this.outCounter = outCounter;
+      this.progressable=progressable;
+      progressBar = conf.getLong(MR_COMBINE_RECORDS_BEFORE_PROGRESS, DEFAULT_MR_COMBINE_RECORDS_BEFORE_PROGRESS);
     }
+    
     public synchronized void setWriter(Writer<K, V> writer) {
       this.writer = writer;
     }
+    
     public synchronized void collect(K key, V value)
         throws IOException {
       outCounter.increment(1);
       writer.append(key, value);
+      if ((outCounter.getValue() % progressBar) == 0) {
+        progressable.progress();
+      }
     }
   }
 

src/test/org/apache/hadoop/mapred/TestCombineOutputCollector.java

@@ -0,0 +1,77 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.mapred;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.mapred.IFile.Writer;
+import org.apache.hadoop.mapred.Task.CombineOutputCollector;
+import org.apache.hadoop.mapred.Task.TaskReporter;
+import org.junit.Test;
+
+public class TestCombineOutputCollector {
+  private CombineOutputCollector<String, Integer> coc;
+
+  @Test
+  public void testCustomCollect() throws Throwable {
+    //mock creation
+    TaskReporter mockTaskReporter = mock(TaskReporter.class);
+    Counters.Counter outCounter = new Counters.Counter();
+    Writer<String, Integer> mockWriter = mock(Writer.class);
+
+    Configuration conf = new Configuration();
+    conf.set("mapred.combine.recordsBeforeProgress", "2");
+    
+    coc = new CombineOutputCollector<String, Integer>(outCounter, mockTaskReporter, conf);
+    coc.setWriter(mockWriter);
+    verify(mockTaskReporter, never()).progress();
+
+    coc.collect("dummy", 1);
+    verify(mockTaskReporter, never()).progress();
+    
+    coc.collect("dummy", 2);
+    verify(mockTaskReporter, times(1)).progress();
+  }
+  
+  @Test
+  public void testDefaultCollect() throws Throwable {
+    //mock creation
+    TaskReporter mockTaskReporter = mock(TaskReporter.class);
+    Counters.Counter outCounter = new Counters.Counter();
+    Writer<String, Integer> mockWriter = mock(Writer.class);
+
+    Configuration conf = new Configuration();
+    
+    coc = new CombineOutputCollector<String, Integer>(outCounter, mockTaskReporter, conf);
+    coc.setWriter(mockWriter);
+    verify(mockTaskReporter, never()).progress();
+
+    for(int i = 0; i < Task.DEFAULT_MR_COMBINE_RECORDS_BEFORE_PROGRESS; i++) {
+    	coc.collect("dummy", i);
+    }
+    verify(mockTaskReporter, times(1)).progress();
+    for(int i = 0; i < Task.DEFAULT_MR_COMBINE_RECORDS_BEFORE_PROGRESS; i++) {
+    	coc.collect("dummy", i);
+    }
+    verify(mockTaskReporter, times(2)).progress();
+  }
+}