RE: Datanode doesn't start but there is no exception in the log

2011-05-13 Thread Panayotis Antonopoulos
...@yahoo.com wrote: Is that all the messages in the datanode log? Do you see any SHUTDOWN message also? -Bharath From: Panayotis Antonopoulos antonopoulos...@hotmail.com To: common-user@hadoop.apache.org Sent: Thursday, May 12, 2011 6:07 PM

RE: Datanode doesn't start but there is no exception in the log

2011-05-13 Thread Panayotis Antonopoulos
To: common-user@hadoop.apache.org When you say freeze you mean there is nothing rolling in the log? Sent from my iPhone On May 13, 2011, at 2:28 AM, Panayotis Antonopoulos antonopoulos...@hotmail.com wrote: There is no shutdown message until I shutdown the DataNode. I used

RE: Datanode doesn't start but there is no exception in the log

2011-05-13 Thread Panayotis Antonopoulos
doesn't start but there is no exception in the log To: common-user@hadoop.apache.org Hello Panayotis, Could you please post a jstack output of your hung process to look into? $ jstack PID of DN # will do. 2011/5/13 Panayotis Antonopoulos antonopoulos...@hotmail.com: There is no other

RE: Datanode doesn't start but there is no exception in the log

2011-05-13 Thread Panayotis Antonopoulos
-user@hadoop.apache.org Actually, only the last mentioned stack matters. Also see: https://issues.apache.org/jira/browse/HDFS-1835 On Fri, May 13, 2011 at 11:15 PM, Harsh J ha...@cloudera.com wrote: Hey, 2011/5/13 Panayotis Antonopoulos antonopoulos...@hotmail.com: 899599744@qtp

RE: Datanode doesn't start but there is no exception in the log

2011-05-13 Thread Panayotis Antonopoulos
I am using the cluster of the Lab of my university, so I have limited access to its settings. It consists of 10 nodes with Intel Xeon CPUs and GNU/Linux 2.6.38 Is there a way to solve the problem without changing the settings of the cluster? I am trying to use the patch that Harsh J sent me

RE: Datanode doesn't start but there is no exception in the log

2011-05-13 Thread Panayotis Antonopoulos
I installed the patch: https://issues.apache.org/jira/browse/HDFS-1835 that Harsh J told me and now everything works great!!! I hope that this change won't create other problems. Thanks to everyone and especially to Harsh J!! I would never find the problem without your help!! From:

Question about InputSampler

2011-05-12 Thread Panayotis Antonopoulos
Hello, I am writing a MR job where the distribution of the Keys emitted by the Map phase is not known beforehand and so I can't create the partitions for the TotalOrderPartitioner. I would like to sample those keys to create the partitions and then run the job that will process the whole

Datanode doesn't start but there is no exception in the log

2011-05-12 Thread Panayotis Antonopoulos
Hello, I am trying to set up Hadoop HDFS in a cluster for the first time. So far I was using pseudo-distributed mode on my PC at home and everything was working perfectly. Tha NameNode starts but the DataNode doesn't start and the log contains the following: 2011-05-13 04:01:13,663 INFO

How to make changes in Hadoop's classes visible

2011-04-29 Thread Panayotis Antonopoulos
Hello, I am a beginner and I have downloaded Hadoop 0.20.2. I would like to make some changes in some of the classes of Hadoop and import them into hadoop-0.20.2-core.jar so that they are visible to the mapreduce programs. What is the best way to do this? What should I do if I find the changes

ChainMapper and ChainReducer: Are the key/value pairs distributed to the nodes of the cluster before each Map phase?

2011-04-29 Thread Panayotis Antonopoulos
Hello, Let' say we have a MR job that uses ChainMapper and ChainReducer like in the following diagram: Input-Map1-Map2-Reduce-Map3-Output The input is split and distributed to the nodes of the cluster before being processed by Map1 phase. Also, before the Reduce phase the key/value pairs are