Konstantin Shvachko created HDFS-4452:
-----------------------------------------
Summary: getAdditionalBlock() can create multiple blocks if the
client times out and retries.
Key: HDFS-4452
URL: https://issues.apache.org/jira/browse/HDFS-4452
Project: Hadoop HDFS
Issue Type: Bug
Components: namenode
Affects Versions: 2.0.2-alpha
Reporter: Konstantin Shvachko
Assignee: Konstantin Shvachko
Priority: Critical
HDFS client tries to addBlock() to a file. If NameNode is busy the client can
timeout and will reissue the same request again. The two requests will race
with each other in {{FSNamesystem.getAdditionalBlock()}}, which can result in
creating two new blocks on the NameNode while the client will know of only one
of them. This eventually results in {{NotReplicatedYetException}} because the
extra block is never reported by any DataNode, which stalls file creation and
puts it in invalid state with an empty block in the middle.
--
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
