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Todd Lipcon commented on HDFS-1965: ----------------------------------- Committed to trunk after re-running the test. It doesn't apply directly to 0.22. Let me format a patch there and upload it soon. > IPCs done using block token-based tickets can't reuse connections > ----------------------------------------------------------------- > > Key: HDFS-1965 > URL: https://issues.apache.org/jira/browse/HDFS-1965 > Project: Hadoop HDFS > Issue Type: Bug > Components: security > Reporter: Todd Lipcon > Assignee: Todd Lipcon > Priority: Critical > Fix For: 0.22.0 > > Attachments: hdfs-1965.txt, hdfs-1965.txt, hdfs-1965.txt > > > This is the reason that TestFileConcurrentReaders has been failing a lot. > Reproducing a comment from HDFS-1057: > The test has a thread which continually re-opens the file which is being > written to. Since the file's in the middle of being written, it makes an RPC > to the DataNode in order to determine the visible length of the file. This > RPC is authenticated using the block token which came back in the > LocatedBlocks object as the security ticket. > When this RPC hits the IPC layer, it looks at its existing connections and > sees none that can be re-used, since the block token differs between the two > requesters. Hence, it reconnects, and we end up with hundreds or thousands of > IPC connections to the datanode. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira