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Allen Wittenauer resolved HDFS-1137. ------------------------------------ Resolution: Not a Problem > Name node is using the write-ahead log improperly > ------------------------------------------------- > > Key: HDFS-1137 > URL: https://issues.apache.org/jira/browse/HDFS-1137 > Project: Hadoop HDFS > Issue Type: Bug > Components: namenode > Reporter: Benjamin Reed > > The Name node is doing the write-ahead log (WAL) (aka edit log) improperly. > Usually when using WAL, changes are written to the log before they are > applied to the state. Currently the Namenode does the WAL after applying the > change. This means that read may see changes before they are durable. A > client may read information and the server fail before the information is > written to the WAL, which results in the client reading state that > disappears. To fix the Namenode should write changes before (aka ahead of) > applying the change. -- This message was sent by Atlassian JIRA (v6.2#6252)