title: Hadoop multi node clusters
body: <p>How to interpret the following log report of tasktracker daemon on slave node of Hadoop ?</p>
  
  <pre><code>2016-02-27 15:59:57,956 INFO org.apache.hadoop.mapred.TaskTracker: Trying to launch : attempt_201602271541_0001_m_000001_0
  2016-02-27 15:59:57,956 INFO org.apache.hadoop.mapred.TaskTracker: In TaskLauncher, current free slots : 2 and trying to launch attempt_201602$
  2016-02-27 15:59:58,194 INFO org.apache.hadoop.mapred.JvmManager: In JvmRunner constructed JVM ID: jvm_201602271541_0001_m_189940062
  2016-02-27 15:59:58,194 INFO org.apache.hadoop.mapred.JvmManager: JVM Runner jvm_201602271541_0001_m_189940062 spawned.
  2016-02-27 15:59:58,555 INFO org.apache.hadoop.mapred.TaskTracker: JVM with ID: jvm_201602271541_0001_m_189940062 given task: attempt_20160227$
  2016-02-27 15:59:59,261 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201602271541_0001_m_000001_0 0.0%
  2016-02-27 15:59:59,262 INFO org.apache.hadoop.mapred.TaskTracker: Task attempt_201602271541_0001_m_000001_0 is done.
  2016-02-27 15:59:59,262 INFO org.apache.hadoop.mapred.TaskTracker: reported output size for attempt_201602271541_0001_m_000001_0  was 0
  2016-02-27 15:59:59,263 INFO org.apache.hadoop.mapred.TaskTracker: addFreeSlot : current free slots : 2
  2016-02-27 15:59:59,309 INFO org.apache.hadoop.mapred.JvmManager: JVM : jvm_201602271541_0001_m_189940062 exited. Number of tasks it ran: 1
  2016-02-27 16:00:00,974 INFO org.apache.hadoop.mapred.TaskTracker: LaunchTaskAction (registerTask): attempt_201602271541_0001_r_000000_0 task'$
  2016-02-27 16:00:00,975 INFO org.apache.hadoop.mapred.TaskTracker: Trying to launch : attempt_201602271541_0001_r_000000_0
  2016-02-27 16:00:00,975 INFO org.apache.hadoop.mapred.TaskTracker: In TaskLauncher, current free slots : 2 and trying to launch attempt_201602$
  2016-02-27 16:00:01,016 INFO org.apache.hadoop.mapred.JvmManager: In JvmRunner constructed JVM ID: jvm_201602271541_0001_r_189940062
  2016-02-27 16:00:01,017 INFO org.apache.hadoop.mapred.JvmManager: JVM Runner jvm_201602271541_0001_r_189940062 spawned.
  2016-02-27 16:00:01,374 INFO org.apache.hadoop.mapred.TaskTracker: JVM with ID: jvm_201602271541_0001_r_189940062 given task: attempt_20160227$
  2016-02-27 16:00:06,662 INFO org.apache.hadoop.mapred.TaskTracker: Sent out 6 bytes for reduce: 0 from map: attempt_201602271541_0001_m_000001$
  2016-02-27 16:00:06,663 INFO org.apache.hadoop.mapred.TaskTracker.clienttrace: src: 10.0.0.3:50060, dest: 10.0.0.3:47317, bytes: 6, op: MAPRED$
  2016-02-27 16:00:07,599 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201602271541_0001_r_000000_0 0.16666667% reduce &gt; copy (1 of 2 at 0$
  2016-02-27 16:00:10,602 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201602271541_0001_r_000000_0 0.16666667% reduce &gt; copy (1 of 2 at 0$
  2016-02-27 16:00:16,605 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201602271541_0001_r_000000_0 0.16666667% reduce &gt; copy (1 of 2 at 0$
  2016-02-27 16:00:22,609 INFO org.apache.hadoop.mapred.TaskTracker: attempt_201602271541_0001_r_000000_0 0.16666667% reduce &gt; copy (1 of 2 at 0$
  $2 at 0.00 MB/s) &gt;
  </code></pre>