Thanks Harsh :) the hadoop system started 3 months ago. so i think it is not in safe mode. i found some old tasks started 10 days ago, the tasks seem blocked by some unknown reason. I killed these tasks now. but i don't know why a task can be blocked and exists so long.
I found another type of exception like this in namenode's node. 2011-08-16 11:25:44,352 INFO org.apache.hadoop.mapred.TaskInProgress: Error from attempt_201106021431_1704_r_000506_1: org.ap ache.hadoop.ipc.RemoteException: org.apache.hadoop.hdfs.server.namenode.LeaseExpiredException: No lease on /walter/send_album s/110816_111850/_temporary/_attempt_201106021431_1704_r_000506_1/part-r-00506 File does not exist. Holder DFSClient_attempt_2 01106021431_1704_r_000506_1 does not have any open files. at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkLease(FSNamesystem.java:1332) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkLease(FSNamesystem.java:1323) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:1251) at org.apache.hadoop.hdfs.server.namenode.NameNode.addBlock(NameNode.java:422) at sun.reflect.GeneratedMethodAccessor17.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:508) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:959) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:955) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:396) at org.apache.hadoop.ipc.Server$Handler.run(Server.java:953) at org.apache.hadoop.ipc.Client.call(Client.java:740) at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:220) at $Proxy1.addBlock(Unknown Source) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) 2011/8/17, Harsh J <ha...@cloudera.com>: > Do you notice anything related in the NameNode logs? One reason for > this is that the NameNode may be in safe mode for some reason, but > there are many other reasons so the NameNode's log would be the best > place to look for exactly why the complete()-op fails. > > On Wed, Aug 17, 2011 at 8:20 AM, Jianxin Wang <wangjx...@gmail.com> wrote: >> hi, >> my job runs once ervey day. but it failed sometimes. >> i checked the log in job tracker. It seems a hdfs error? >> thanks a lot! >> >> 2011-08-16 21:07:13,247 INFO org.apache.hadoop.mapred.TaskInProgress: >> Error from attempt_201106021431_1719_r_000498_1: org.ap >> ache.hadoop.ipc.RemoteException: java.io.IOException: Could not >> complete write to file /xxx/yyy/110816_210016/_tem >> porary/_attempt_201106021431_1719_r_000498_1/part-r-00498 by >> DFSClient_attempt_201106021431_1719_r_000498_1 >> at >> org.apache.hadoop.hdfs.server.namenode.NameNode.complete(NameNode.java:449) >> at sun.reflect.GeneratedMethodAccessor12.invoke(Unknown Source) >> at >> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) >> at java.lang.reflect.Method.invoke(Method.java:597) >> at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:508) >> at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:959) >> at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:955) >> at java.security.AccessController.doPrivileged(Native Method) >> at javax.security.auth.Subject.doAs(Subject.java:396) >> at org.apache.hadoop.ipc.Server$Handler.run(Server.java:953) >> >> at org.apache.hadoop.ipc.Client.call(Client.java:740) >> at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:220) >> at $Proxy1.complete(Unknown Source) >> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) >> at >> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) >> at >> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) >> at java.lang.reflect.Method.invoke(Method.java:597) >> at >> org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:82) >> at >> org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:59) >> at $Proxy1.complete(Unknown Source) >> at >> org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.closeInternal(DFSClient.java:3264) >> at >> org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.close(DFSClient.java:3188) >> at >> org.apache.hadoop.fs.FSDataOutputStream$PositionCache.close(FSDataOutputStream.java:61) >> at >> org.apache.hadoop.fs.FSDataOutputStream.close(FSDataOutputStream.java:86) >> at org.apache.hadoop.io.SequenceFile$Writer.close(SequenceFile.java:959) >> at >> org.apache.hadoop.io.SequenceFile$BlockCompressWriter.close(SequenceFile.java:1290) >> at >> org.apache.hadoop.mapreduce.lib.output.SequenceFileOutputFormat$1.close(SequenceFileOutputFormat.java:78) >> at org.apache.hadoop.mapred.ReduceTask.runNewReducer(ReduceTask.java:567) >> at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:408) >> at org.apache.hadoop.mapred.Child.main(Child.java:170) >> > > > > -- > Harsh J >