Hi friends,
I have made a cluster of 3 machines, one of them is master, and other 2
slaves. I executed a mapreduce job on master but after Map, the execution
terminates and Reduce doesn't happen. I have checked dfs and no output
folder gets created.
this is the error I see
08/03/10 10:35:21 INFO mapred.JobClient: Task Id :
task_200803101001_0001_m_000064_0, Status : FAILED
java.lang.OutOfMemoryError: Java heap space
at java.io.ByteArrayOutputStream.write(ByteArrayOutputStream.java
:95)
at java.io.DataOutputStream.write(DataOutputStream.java:90)
at org.apache.hadoop.io.Text.write(Text.java:243)
at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(
MapTask.java:347)
at org.apache.hadoop.examples.WordCount$MapClass.map(WordCount.java
:72)
at org.apache.hadoop.examples.WordCount$MapClass.map(WordCount.java
:59)
at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:50)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:192)
at org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java
:1787)
08/03/10 10:35:22 INFO mapred.JobClient: map 55% reduce 17%
08/03/10 10:35:31 INFO mapred.JobClient: map 56% reduce 17%
08/03/10 10:35:51 INFO mapred.JobClient: map 57% reduce 17%
08/03/10 10:36:04 INFO mapred.JobClient: map 58% reduce 17%
08/03/10 10:36:07 INFO mapred.JobClient: map 57% reduce 17%
08/03/10 10:36:07 INFO mapred.JobClient: Task Id :
task_200803101001_0001_m_000071_0, Status : FAILED
java.lang.OutOfMemoryError: Java heap space
at java.io.ByteArrayOutputStream.write(ByteArrayOutputStream.java
:95)
at java.io.DataOutputStream.write(DataOutputStream.java:90)
at org.apache.hadoop.io.Text.write(Text.java:243)
at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.collect(
MapTask.java:347)
at org.apache.hadoop.examples.WordCount$MapClass.map(WordCount.java
:72)
at org.apache.hadoop.examples.WordCount$MapClass.map(WordCount.java
:59)
at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:50)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:192)
at org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java
:1787)
though it tries to overcome this problem but the mapreduce application
doesn't create output, can anyone tell me why is this happening?
Thanks
