Reducers fail with OutOfMemoryError while copying Map outputs
-------------------------------------------------------------
Key: HADOOP-6357
URL: https://issues.apache.org/jira/browse/HADOOP-6357
Project: Hadoop Common
Issue Type: Bug
Affects Versions: 0.20.0
Reporter: Chandra Prakash Bhagtani
Reducers fail while copying Map outputs with following exception
java.lang.OutOfMemoryError: Java heap space at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$MapOutputCopier.shuffleInMemory(ReduceTask.java:1539)
at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$MapOutputCopier.getMapOutput(ReduceTask.java:1432)
at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$MapOutputCopier.copyOutput(ReduceTask.java:1285)
at
org.apache.hadoop.mapred.ReduceTask$ReduceCopier$MapOutputCopier.run(ReduceTask.java:1216)
,Error:
Reducer's memory usage keeps on increasing and ultimately exceeds -Xmx value
I even tried with -Xmx6.5g to each reducer but it's still failing
While looking into the reducer logs, I found that reducers were doing
shuffleInMemory every time, rather than doing shuffleOnDisk
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
