Add addtional: Our MR version is 1.2.1, not 1.0.4
There is no useful information in the JT log. On Fri, Jan 3, 2014 at 12:20 PM, Azuryy Yu <azury...@gmail.com> wrote: > Hi, > > Our prod cluster met some issues recently, > All map tasks finished successfully, but reduce task hanged. > > but It's not happened on all TaskTrackers, only sometimes. we used > mapred-1.0.4 > > There is "0.0% reduce > copy >" forever until kill task manually. > > reduce logs on the TaskTracker: > hadoop-hadoop-tasktracker-10-200-91-186.out:14/01/03 06:13:57 INFO > mapred.TaskTracker: JVM with ID: jvm_201312201200_34795_r_-365330778 given > task: attempt_201312201200_34795_r_000000_0 > hadoop-hadoop-tasktracker-10-200-91-186.out:14/01/03 06:14:04 INFO > mapred.TaskTracker: attempt_201312201200_34795_r_000000_0 0.0% reduce > > copy > > hadoop-hadoop-tasktracker-10-200-91-186.out:14/01/03 06:14:08 INFO > mapred.TaskTracker: attempt_201312201200_34795_r_000000_0 0.0% reduce > > copy > > hadoop-hadoop-tasktracker-10-200-91-186.out:14/01/03 06:14:14 INFO > mapred.TaskTracker: attempt_201312201200_34795_r_000000_0 0.0% reduce > > copy > > hadoop-hadoop-tasktracker-10-200-91-186.out:14/01/03 06:14:17 INFO > mapred.TaskTracker: attempt_201312201200_34795_r_000000_0 0.0% reduce > > copy > > hadoop-hadoop-tasktracker-10-200-91-186.out:14/01/03 06:14:23 INFO > mapred.TaskTracker: attempt_201312201200_34795_r_000000_0 0.0% reduce > > copy > >
