记一次Hive任务hang住的问题(1)

1 问题背景

beeline偶尔出现任务进程卡住, 长时间等待无响应的情况.下面尝试进行分析及定位代码位置.

2 分析步骤

2.1 首先定位进程的

这里我们很明确是HiveServer2进程:
ps -ef | grep hiveserver2
或
jps

2.2 定位繁忙的线程

top -Hp
如下, 看出PID是 117426

top - 17:10:29 up 69 days, 39 min,  3 users,  load average: 8.70, 11.67, 10.29
Threads: 604 total,   5 running, 599 sleeping,   0 stopped,   0 zombie
%Cpu(s): 14.7 us,  1.6 sy,  0.0 ni, 83.5 id,  0.0 wa,  0.0 hi,  0.2 si,  0.0 st
KiB Mem : 26389854+total, 60735220 free, 12119641+used, 81966912 buff/cache
KiB Swap:        0 total,        0 free,        0 used. 13862755+avail Mem

   PID USER      PR  NI    VIRT    RES    SHR S %CPU %MEM     TIME+ COMMAND
117426 hadoop     20   0   68.4g  54.0g  15208 R 99.7 21.5 131:39.68 java
 46085 hadoop     20   0   68.4g  54.0g  15208 S  5.0 21.5   0:00.32 java
 49034 hadoop     20   0   68.4g  54.0g  15208 S  5.0 21.5   0:00.15 java

2.3 抓取服务进程jstack现场并分析

将jstack现场抓取到文件jstack.js中:
jstack -l > jstack.js

需要将第三步中繁忙的线程ID转为十六进制:printf "%x\n" 117426

[hadoop@hadoop-server /tmp]$ printf "%x\n" 117426
1cab2

然后在jstack.js中查找该线程信息:
可以看出是在CombineFileInputFormat.getSplits 时hang住了,下面就可以从代码分析为什么会hang住.初步判断是因为文件太大,导致splits时hang住.

"Thread-17999" #19884 prio=5 os_prio=0 tid=0x00007f9021c4f800 nid=0x1cab2 runnable [0x00007f9001e74000]
   java.lang.Thread.State: RUNNABLE
        at org.apache.hadoop.mapreduce.lib.input.CombineFileInputFormat.getSplits(CombineFileInputFormat.java:237)
        at org.apache.hadoop.mapred.lib.CombineFileInputFormat.getSplits(CombineFileInputFormat.java:76)
        at org.apache.hadoop.hive.shims.HadoopShimsSecure$CombineFileInputFormatShim.getSplits(HadoopShimsSecure.java:309)
        at org.apache.hadoop.hive.ql.io.CombineHiveInputFormat.getCombineSplits(CombineHiveInputFormat.java:470)
        at org.apache.hadoop.hive.ql.io.CombineHiveInputFormat.getSplits(CombineHiveInputFormat.java:571)
        at org.apache.hadoop.mapreduce.JobSubmitter.writeOldSplits(JobSubmitter.java:347)
        at org.apache.hadoop.mapreduce.JobSubmitter.writeSplits(JobSubmitter.java:338)
        at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:196)
        at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1290)
        at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1287)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:422)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1923)
        at org.apache.hadoop.mapreduce.Job.submit(Job.java:1287)
        at org.apache.hadoop.mapred.JobClient$1.run(JobClient.java:575)
        at org.apache.hadoop.mapred.JobClient$1.run(JobClient.java:570)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:422)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1923)
        at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:570)
        at org.apache.hadoop.mapred.JobClient.submitJob(JobClient.java:561)
        at org.apache.hadoop.hive.ql.exec.mr.ExecDriver.execute(ExecDriver.java:434)
        at org.apache.hadoop.hive.ql.exec.mr.MapRedTask.execute(MapRedTask.java:138)
        at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:160)
        at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:100)
        at org.apache.hadoop.hive.ql.exec.TaskRunner.run(TaskRunner.java:80)

   Locked ownable synchronizers:
        - None