我尝试在linux（ubuntu虚拟机）中使用hadoop map reduce，如下链接
我在一个示例文件上运行了wordcount示例。进程意外终止。如何调试？
起初，我得到了一个大数据集内存不足的错误。

15/11/28 19:24:27 INFO mapred.Task:  Using ResourceCalculatorProcessTree : [ ]
15/11/28 19:24:27 INFO mapred.MapTask: Processing split: hdfs://localhost:54310/user/hduser/eg2/a.txt:0+1538
Java HotSpot(TM) 64-Bit Server VM warning: INFO: os::commit_memory(0x00000000e6093000, 104861696, 0) failed; error='Cannot allocate memory' (errno=12)

# 

# There is insufficient memory for the Java Runtime Environment to continue.

# Native memory allocation (malloc) failed to allocate 104861696 bytes for committing reserved memory.

# An error report file with more information is saved as:

# /usr/local/hadoop/hs_err_pid7516.log

因此，我缩小了我的文件大小，并再次尝试，结果意外终止。

hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-2.6.0.jar  wordcount /user/hduser/eg2/ /user/hduser/eg2/eg2-output2
......
......
15/11/28 18:55:44 INFO mapred.LocalJobRunner: Waiting for map tasks
15/11/28 18:55:44 INFO mapred.LocalJobRunner: Starting task: attempt_local1996683170_0001_m_000000_0
15/11/28 18:55:44 INFO mapred.Task:  Using ResourceCalculatorProcessTree : [ ]
15/11/28 18:55:44 INFO mapred.MapTask: Processing split: hdfs://localhost:54310/user/hduser/eg2/a.txt:0+1538
15/11/28 18:55:45 INFO mapreduce.Job: Job job_local1996683170_0001 running in uber mode : false
15/11/28 18:55:45 INFO mapreduce.Job:  map 0% reduce 0%
Killed

为什么进程会被终止？