I'm not sure, but I've seen TT failures from jobs that blocked on computationally intense operation (GC?) or large I/O.
Take care, -stu -----Original Message----- From: baran cakici <barancak...@gmail.com> Date: Wed, 16 Mar 2011 17:52:10 To: <hdfs-user@hadoop.apache.org> Reply-To: hdfs-user@hadoop.apache.org Subject: Lost Task Tracker because of no heartbeat Hi Everyone, I make a Project with Hadoop-MapRedeuce for my master-Thesis. I have a strange problem on my System. First of all, I use Hadoop-0.20.2 on Windows XP Pro with Eclipse Plug-In. When I start a job with big Input(4GB - it`s may be not to big, but algorithm require some time), then i lose my Task Tracker in several minutes or seconds. I mean, "Seconds since heartbeat" increase and then after 600 Seconds I lose TaskTracker. I read somewhere, that can be occured because of small number of open files (ulimit -n). I try to increase this value, but i can write as max value in Cygwin 3200.(ulimit -n 3200) and default value is 256. Actually I don`t know, is it helps or not. In my job and task tracker.log have I some Errors, I posted those to. Jobtracker.log -Call to localhost/127.0.0.1:9000 failed on local exception: java.io.IOException: An existing connection was forcibly closed by the remote host another : - 2011-03-15 12:13:30,718 INFO org.apache.hadoop.mapred.JobTracker: attempt_201103151143_0002_m_000091_0 is 97125 ms debug. 2011-03-15 12:16:50,718 INFO org.apache.hadoop.mapred.JobTracker: attempt_201103151143_0002_m_000091_0 is 297125 ms debug. 2011-03-15 12:20:10,718 INFO org.apache.hadoop.mapred.JobTracker: attempt_201103151143_0002_m_000091_0 is 497125 ms debug. 2011-03-15 12:23:30,718 INFO org.apache.hadoop.mapred.JobTracker: attempt_201103151143_0002_m_000091_0 is 697125 ms debug. Error launching task Lost tracker 'tracker_apple:localhost/127.0.0.1:2654' there are my logs(jobtracker.log, tasktracker.log ...) in attachment I need really Help, I don`t have so much time for my Thessis. Thanks a lot for your Helps, Baran
