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Tsz Wo (Nicholas), SZE commented on HDFS-3979: ---------------------------------------------- The patch moves ack to the end in order to fix the sync semantics. I think it will decrease the performance for non-sync write. How about keeping enqueue early when syncBlock == false? > Fix hsync and hflush semantics. > ------------------------------- > > Key: HDFS-3979 > URL: https://issues.apache.org/jira/browse/HDFS-3979 > Project: Hadoop HDFS > Issue Type: Bug > Components: data-node, hdfs client > Affects Versions: 0.22.0, 0.23.0, 2.0.0-alpha > Reporter: Lars Hofhansl > Assignee: Lars Hofhansl > Attachments: hdfs-3979-sketch.txt, hdfs-3979-v2.txt, hdfs-3979-v3.txt > > > See discussion in HDFS-744. The actual sync/flush operation in BlockReceiver > is not on a synchronous path from the DFSClient, hence it is possible that a > DN loses data that it has already acknowledged as persisted to a client. > Edit: Spelling. -- 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