Hello everyone,
I have encountered the following error when I try to use randomwriter
(http://wiki.apache.org/lucene-hadoop/RandomWriter)
I also changed the configuration to
Test.randomwriter.mpas_per_host=5
Test.randomwriter.bytes_per_map=1024*1024
In short, I am trying to generate only one megabyte of data
After running
bin/hadoop jar hadoop-0.11.2-examples.jar randomwriter 030307kuku RW.conf,
here is part of the error message:
07/03/01 09:21:31 INFO mapred.JobClient: map 100% reduce 100%
07/03/01 09:21:31 INFO mapred.JobClient: Task Id :
task_0003_m_000000_3, Status : FAILED
07/03/01 09:21:31 INFO mapred.JobClient: 07/03/01 09:21:27 WARN
mapred.TaskTracker: Error running child
org.apache.hadoop.ipc.RemoteException: java.io.IOException: failed to create
file /user/root/030307kuku/part000000 on client localhost.localdomain
because target-length is 0, below MIN_REPLICATION (1)
at
org.apache.hadoop.dfs.FSNamesystem.startFile(FSNamesystem.java:695)
at org.apache.hadoop.dfs.NameNode.create(NameNode.java:248)
at sun.reflect.GeneratedMethodAccessor9.invoke(Unknown Source)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl
.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:337)
at org.apache.hadoop.ipc.Server
It seems that the namenode has problem creating new files to store results.
Yet, what troubles (maybe confuses) me is the fact that I just finished
running sample grep programs without any error.
Currently, there are 3 datanodes and one of them as namenode. I have run 5
sample grep programs concurrently and they all finished fine most of time.
Sometimes the progresses would halt for 5 grep programs and I will need to
reboot every node and start it over again. Does anybody know how to debug
or fix this kind of problem?? Thank you.
Best Regards
Richard Yang
richardyang@richardyang.net
kusanagiyang@gmail.com
