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# Apache Hadoop  1.0.0 Release Notes

These release notes cover new developer and user-facing incompatibilities, important issues, features, and major improvements.


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* [HADOOP-7923](https://issues.apache.org/jira/browse/HADOOP-7923) | *Major* | **Automatically update doc versions**

Docs version number is now automatically updated by reference to the build number.


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* [HADOOP-7740](https://issues.apache.org/jira/browse/HADOOP-7740) | *Minor* | **security audit logger is not on by default, fix the log4j properties to enable the logger**

Fixed security audit logger configuration. (Arpit Gupta via Eric Yang)


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* [HADOOP-7728](https://issues.apache.org/jira/browse/HADOOP-7728) | *Major* | **hadoop-setup-conf.sh should be modified to enable task memory manager**

Enable task memory management to be configurable via hadoop config setup script.


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* [HDFS-2316](https://issues.apache.org/jira/browse/HDFS-2316) | *Major* | **[umbrella] WebHDFS: a complete FileSystem implementation for accessing HDFS over HTTP**

Provide WebHDFS as a complete FileSystem implementation for accessing HDFS over HTTP.
Previous hftp feature was a read-only FileSystem and does not provide "write" accesses.


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* [HDFS-2246](https://issues.apache.org/jira/browse/HDFS-2246) | *Major* | **Shortcut a local client reads to a Datanodes files directly**

1. New configurations
a. dfs.block.local-path-access.user is the key in datanode configuration to specify the user allowed to do short circuit read.
b. dfs.client.read.shortcircuit is the key to enable short circuit read at the client side configuration.
c. dfs.client.read.shortcircuit.skip.checksum is the key to bypass checksum check at the client side.
2. By default none of the above are enabled and short circuit read will not kick in.
3. If security is on, the feature can be used only for user that has kerberos credentials at the client, therefore map reduce tasks cannot benefit from it in general.


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* [HDFS-617](https://issues.apache.org/jira/browse/HDFS-617) | *Major* | **Support for non-recursive create() in HDFS**

New DFSClient.create(...) allows option of not creating missing parent(s).



