Question

我是使用Hadoop流式传输Python的新手。我成功地运行了大多数参考文献中解释的wordcount示例。但是，当我开始使用我自己编写的一个小python脚本时，它显示错误，即使代码的功能几乎没有。

执行命令时的错误部分是：

    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)
14/12/13 01:47:31 INFO mapred.LocalJobRunner: map task executor complete.
14/12/13 01:47:31 WARN mapred.LocalJobRunner: job_local174189774_0001
java.lang.Exception: java.lang.RuntimeException: PipeMapRed.waitOutputThreads(): subprocess failed with code 2
    at org.apache.hadoop.mapred.LocalJobRunner$Job.runTasks(LocalJobRunner.java:462)
    at org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:522)
Caused by: java.lang.RuntimeException: PipeMapRed.waitOutputThreads(): subprocess failed with code 2
    at org.apache.hadoop.streaming.PipeMapRed.waitOutputThreads(PipeMapRed.java:320)
    at org.apache.hadoop.streaming.PipeMapRed.mapRedFinished(PipeMapRed.java:533)
    at org.apache.hadoop.streaming.PipeMapper.close(PipeMapper.java:130)
    at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:61)
    at org.apache.hadoop.streaming.PipeMapRunner.run(PipeMapRunner.java:34)
    at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:430)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:342)
    at org.apache.hadoop.mapred.LocalJobRunner$Job$MapTaskRunnable.run(LocalJobRunner.java:243)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    at java.util.concurrent.FutureTask.run(FutureTask.java:262)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)
14/12/13 01:47:32 INFO mapreduce.Job: Job job_local174189774_0001 failed with state FAILED due to: NA
14/12/13 01:47:32 INFO mapreduce.Job: Counters: 0
14/12/13 01:47:32 ERROR streaming.StreamJob: Job not Successful!
Streaming Command Failed!

map.py文件如下：

    import sys
    for line in sys.stdin:
        line = line.strip()
        review_lines = line.split('\n')
        for r in review_lines:
            review = r.split('\t')
            print '%s\t%s' % (review[0], review[1])

red.py文件如下：

import sys
for line in sys.stdin:
    line = line.strip()
    word = line.split('\t')
    print '%s\t%d' %(word[0], int(word[1]) % 2)

我提供的输入是：（input_file.txt）

用于运行该过程的命令是：

hadoop jar /usr/local/hadoop/share/hadoop/tools/lib/hadoop-streaming-2.4.0.jar -file /home/hduser/map.py -mapper /home/hduser/map.py -file /home/hduser/red.py -reducer /home/hduser/red.py -input /user/hduser/input_file.txt -output /user/hduser/output_file.txt

Answer 1

您可以尝试将它放在脚本的顶部：

 #!/usr/bin/env python

Answer 2

#!/usr/bin/python

为我工作。

Hadoop Streaming命令失败作业未成功

2 个答案: