private String getWorkerId() {
    StringBuilder name = new StringBuilder(this.hostName);
    name.append("-");
    name.append(getId());
    return name.toString();
  }
Finds the next compaction and executes it. The main thread might interrupt the execution of this method
in case of timeout.
@param collectGenericStats If true then for both MR and Query based compaction the stats are regenerated
@param collectMrStats If true then for MR compaction the stats are regenerated
@return Returns true, if there was compaction in the queue, and we started working on it.
ql/src/java/org/apache/hadoop/hive/ql/txn/compactor/Worker.java