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https://issues.apache.org/jira/browse/HDFS-1137?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Allen Wittenauer resolved HDFS-1137.
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    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.



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