title: MapReduce jobs in hive-0.8.1-cdh4.0.1 Failed.
body: <p>Queries in <strong>hive-0.8.1-cdh4.0.1</strong> that invoke the Reducer results in Task Failed.
  The queries having MAPJOIn is working fine but JOIN gives error.</p>
  
  <p>eg:</p>
  
  <pre><code> hive&gt; select count(*) from table1;    
         Total MapReduce jobs = 1    
         Launching Job 1 out of 1
         Number of reduce tasks determined at compile time: 1        
         12/10/15 23:07:02 WARN conf.Configuration: mapred.job.name is deprecated. Instead, use mapreduce.job.name     
         12/10/15 23:07:02 WARN conf.Configuration: mapred.system.dir is deprecated. Instead, use mapreduce.jobtracker.system.dir    
         12/10/15 23:07:02 WARN conf.Configuration: mapred.local.dir is deprecated. Instead, use mapreduce.cluster.local.dir   
         12/10/15 23:07:02 WARN conf.HiveConf: hive-site.xml not found on CLASSPATH    
         WARNING: org.apache.hadoop.metrics.jvm.EventCounter is deprecated. Please use org.apache.hadoop.log.metrics.EventCounter in all the log4j.properties files.    
         Execution log at: /tmp/XXXX    
         /XXXX_20121015230707_c93521d0-4a97-4972-92b9-0fdd3ab42e5f.log    
         SLF4J: Class path contains multiple SLF4J bindings.    
         SLF4J: Found binding in [jar:file:/home/XXXX/hadoop-2.0.0-cdh4.0.1/share/hadoop/common/lib/slf4j-log4j12-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]    
         SLF4J: Found binding in [jar:file:/home/XXXX/hive-0.8.1-cdh4.0.1/lib/slf4j-log4j12-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]    
         SLF4J: See &lt;http://www.slf4j.org/codes.html#multiple_bindings&gt; for an explanation.
         Job running in-process (local Hadoop)     
         Hadoop job information for null: number of mappers: 0; number of reducers: 0    
         2012-10-15 23:07:04,721 null map = 0%,  reduce = 0%    
         Ended Job = job_local_0001 with errors    
         Error during job, obtaining debugging information...    
         **Execution failed with exit status: 2**    
         Obtaining error information    
         **Task failed!**    
         Task ID:    
         Stage-1    
         Logs:    
         /tmp/XXXX/hive.log    
         FAILED: Execution Error, return code 2 from      org.apache.hadoop.hive.ql.exec.MapRedTask       
  </code></pre>
  
  <p>The log file shows that its due to Java heap space problem.</p>
  
  <pre><code>**java.lang.Exception: java.lang.OutOfMemoryError: Java heap space**
      at org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:400)
  Caused by: java.lang.OutOfMemoryError: Java heap space
      at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.&lt;init&gt;(MapTask.java:912)
      at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:391)
      at org.apache.hadoop.mapred.MapTask.run(MapTask.java:334)
      at org.apache.hadoop.mapred.LocalJobRunner$Job$MapTaskRunnable.run(LocalJobRunner.java:232)
      at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
      at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
      at java.util.concurrent.FutureTask.run(FutureTask.java:138)
      at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
      at java.lang.Thread.run(Thread.java:662)
  </code></pre>