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Fengdong Yu commented on MAPREDUCE-4857: ---------------------------------------- bq. But, can you tell me how will i build this code. under your $HADOOP_HOME/: mvn -Dmaven.test.skip.exec=true package > Fix 126 error during map/reduce phase > ------------------------------------- > > Key: MAPREDUCE-4857 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-4857 > Project: Hadoop Map/Reduce > Issue Type: Bug > Affects Versions: 1.0.4 > Reporter: Fengdong Yu > Fix For: 1.0.4 > > Attachments: MAPREDUCE-4857.patch > > > There is rare happenings during map or reduce phase, but mostly in map phase, > the Exception messages: > java.lang.Throwable: Child Error > at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:271) > Caused by: java.io.IOException: Task process exit with nonzero status of 126. > at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:258) > and error logs are cleaned, so It's very hard to debug. > but I compared DefaultTaskController.java with 0.22, they use "bash command" > to start the job scritp, but 1.0.4 use "bash, "-c", command". > I removed "-c", everything is ok, 126 error code never happen again. > I read man document of bash, it indicates when fork a new thread with write > command, another thread with "bash -c" also has a writable fd. so I think it > could return 126 status occasionally. > So, there is only one line fix for this issue. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira