在hadoop多节点集群设置中,从作业日志到$ {hadoop.tmp.dir}创建符号链接失败

Question

当我在3节点集群hadoop中运行简单的wordcount示例时,我得到以下错误.我检查了必要文件夹的所有写/读权限.此错误不会停止mapreduce作业,但所有工作负载都会转移到群集中的一台计算机上,而其他两台计算机在任务到达时会产生相同的错误.

12/09/13 09:38:37 INFO mapred.JobClient: Task Id : attempt_201209121718_0006_m_000008_0,Status : FAILED
java.lang.Throwable: Child Error
    at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:271)
Caused by: java.io.IOException: Creation of symlink from /hadoop/libexec/../logs/userlogs/job_201209121718_0006/attempt_201209121718_0006_m_000008_0 to /hadoop/hadoop-datastore
/mapred/local/userlogs/job_201209121718_0006/attempt_201209121718_0006_m_000008_0 failed.
    at org.apache.hadoop.mapred.TaskLog.createTaskAttemptLogDir(TaskLog.java:110)
    at org.apache.hadoop.mapred.DefaultTaskController.createLogDir(DefaultTaskController.java:71)
    at org.apache.hadoop.mapred.TaskRunner.prepareLogFiles(TaskRunner.java:316)
    at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:228)

12/09/13 09:38:37 WARN mapred.JobClient: Error reading task outputhttp://peter:50060/tasklog?plaintext=true&attemptid=attempt_201209121718_0006_m_000008_0&filter=stdout
12/09/13 09:38:37 WARN mapred.JobClient: Error reading task outputhttp://peter:50060/tasklog?plaintext=true&attemptid=attempt_201209121718_0006_m_000008_0&filter=stderr

那个错误是什么？

Answer 1

java.lang.Throwable：子错误

org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:271)

分配给任务跟踪器的内存似乎大于节点的实际内存。检查此链接说明