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郭同 commented on HDFS-2576: -------------------------- I have the same problem,Thank you very much ... > Namenode should have a favored nodes hint to enable clients to have control > over block placement. > ------------------------------------------------------------------------------------------------- > > Key: HDFS-2576 > URL: https://issues.apache.org/jira/browse/HDFS-2576 > Project: Hadoop HDFS > Issue Type: New Feature > Components: hdfs-client, namenode > Reporter: Pritam Damania > Assignee: Devaraj Das > Fix For: 2.1.0-beta > > Attachments: hdfs-2576-1.txt, hdfs-2576-trunk-1.patch, > hdfs-2576-trunk-2.patch, hdfs-2576-trunk-7.1.patch, hdfs-2576-trunk-7.patch, > hdfs-2576-trunk-8.1.patch, hdfs-2576-trunk-8.2.patch, > hdfs-2576-trunk-8.3.patch, hdfs-2576-trunk-8.patch > > > Sometimes Clients like HBase are required to dynamically compute the > datanodes it wishes to place the blocks for a file for higher level of > locality. For this purpose there is a need of a way to give the Namenode a > hint in terms of a favoredNodes parameter about the locations where the > client wants to put each block. The proposed solution is a favored nodes > parameter in the addBlock() method and in the create() file method to enable > the clients to give the hints to the NameNode about the locations of each > replica of the block. Note that this would be just a hint and finally the > NameNode would look at disk usage, datanode load etc. and decide whether it > can respect the hints or not. -- This message was sent by Atlassian JIRA (v6.3.4#6332)