[TEZ-3824] MRCombiner creates new JobConf copy per spill

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.9.2, 0.10.0
• Hadoop Flags: Reviewed
• Assignee: Jonathan Turner Eagles
• Reporter: Jonathan Turner Eagles
• Created: 29/Aug/17 21:41
• Updated: 19/Apr/19 19:21
• Resolved: 14/May/18 18:23

Description

scope-57(HASH_JOIN) stack trace

"SpillThread {scope_60_" #99 daemon prio=5 os_prio=0 tid=0x00007f2128d21800 nid=0x7487 runnable [0x00007f21154c4000]
   java.lang.Thread.State: RUNNABLE
        at java.util.concurrent.ConcurrentHashMap.putVal(ConcurrentHashMap.java:1012)
        at java.util.concurrent.ConcurrentHashMap.putAll(ConcurrentHashMap.java:1084)
        at java.util.concurrent.ConcurrentHashMap.<init>(ConcurrentHashMap.java:852)
        at org.apache.hadoop.conf.Configuration.<init>(Configuration.java:728)
        - locked <0x00000000d1dc5240> (a org.apache.hadoop.conf.Configuration)
        at org.apache.hadoop.mapred.JobConf.<init>(JobConf.java:442)
        at org.apache.hadoop.mapreduce.task.JobContextImpl.<init>(JobContextImpl.java:67)
        at org.apache.hadoop.mapreduce.task.TaskAttemptContextImpl.<init>(TaskAttemptContextImpl.java:49)
        at org.apache.hadoop.mapreduce.task.TaskInputOutputContextImpl.<init>(TaskInputOutputContextImpl.java:54)
        at org.apache.hadoop.mapreduce.task.ReduceContextImpl.<init>(ReduceContextImpl.java:95)
        at org.apache.tez.mapreduce.combine.MRCombiner.createReduceContext(MRCombiner.java:237)
        at org.apache.tez.mapreduce.combine.MRCombiner.runNewCombiner(MRCombiner.java:181)
        at org.apache.tez.mapreduce.combine.MRCombiner.combine(MRCombiner.java:115)
        at org.apache.tez.runtime.library.common.sort.impl.ExternalSorter.runCombineProcessor(ExternalSorter.java:313)
        at org.apache.tez.runtime.library.common.sort.impl.dflt.DefaultSorter.spill(DefaultSorter.java:937)
        at org.apache.tez.runtime.library.common.sort.impl.dflt.DefaultSorter.sortAndSpill(DefaultSorter.java:861)
        at org.apache.tez.runtime.library.common.sort.impl.dflt.DefaultSorter$SpillThread.run(DefaultSorter.java:780)

JobConf copy construction for tez

  public JobContextImpl(Configuration conf, JobID jobId) {
    if (conf instanceof JobConf) {
      this.conf = (JobConf)conf;
    } else {
--->this.conf = new JobConf(conf);<----
    }
    this.jobId = jobId;
    this.credentials = this.conf.getCredentials();
    try {
      this.ugi = UserGroupInformation.getCurrentUser();
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
}