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dhruba borthakur commented on HDFS-744: --------------------------------------- We need this functionality for HBase clusters. When HBase writes data to a HLog?HFile, it better be persisted on disk, otherwise there could be data loss when a non-trivial number of datanodes are power-cycled simultaneously. > Support hsync in HDFS > --------------------- > > Key: HDFS-744 > URL: https://issues.apache.org/jira/browse/HDFS-744 > Project: Hadoop HDFS > Issue Type: New Feature > Reporter: Hairong Kuang > > HDFS-731 implements hsync by default as hflush. As descriibed in HADOOP-6313, > the real expected semantics should be "flushes out to all replicas and all > replicas have done posix fsync equivalent - ie the OS has flushed it to the > disk device (but the disk may have it in its cache)." This jira aims to > implement the expected behaviour. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira