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Ravi Prakash commented on HDFS-1172: ------------------------------------ I am able to consistently reproduce this issue with the following command on an 80 node cluster: hadoop jar $HADOOP_PREFIX/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-*-tests.jar SliveTest -baseDir /user/someUser/slive -duration 120 -dirSize 122500 -files 122500 -maps 560 -reduces 1 -seed 1 -ops 100 -readSize 1048576,1048576 -writeSize 1048576,1048576 -appendSize 1048576,1048576 -replication 1,1 -blockSize 1024,1024 -delete 0,uniform -create 100,uniform -mkdir 0,uniform -rename 0,uniform -append 0,uniform -ls 0,uniform -read 0,uniform This litters the task logs with the NotReplicatedYetException at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:1268) at org.apache.hadoop.hdfs.server.namenode.NameNode.addBlock(NameNode.java:469) > Blocks in newly completed files are considered under-replicated too quickly > --------------------------------------------------------------------------- > > Key: HDFS-1172 > URL: https://issues.apache.org/jira/browse/HDFS-1172 > Project: Hadoop HDFS > Issue Type: Bug > Components: namenode > Affects Versions: 0.21.0 > Reporter: Todd Lipcon > Fix For: 0.24.0 > > Attachments: HDFS-1172.patch, hdfs-1172.txt, hdfs-1172.txt, > replicateBlocksFUC1.patch, replicateBlocksFUC1.patch, replicateBlocksFUC.patch > > > I've seen this for a long time, and imagine it's a known issue, but couldn't > find an existing JIRA. It often happens that we see the NN schedule > replication on the last block of files very quickly after they're completed, > before the other DNs in the pipeline have a chance to report the new block. > This results in a lot of extra replication work on the cluster, as we > replicate the block and then end up with multiple excess replicas which are > very quickly deleted. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira