Why does ./bin/spark-shell give WARN NativeCodeLoader: Unable to load native-hadoop library for your platform?

Question

On Mac OS X, I compiled Spark from the sources using the following command:

jacek:~/oss/spark
$ SPARK_HADOOP_VERSION=2.4.0 SPARK_YARN=true SPARK_HIVE=true SPARK_GANGLIA_LGPL=true xsbt
...

[info] Set current project to root (in build file:/Users/jacek/oss/spark/)
> ; clean ; assembly
...
[info] Packaging /Users/jacek/oss/spark/examples/target/scala-2.10/spark-examples-1.0.0-SNAPSHOT-hadoop2.4.0.jar ...
[info] Done packaging.
[info] Done packaging.
[success] Total time: 1964 s, completed May 9, 2014 5:07:45 AM

When I started ./bin/spark-shell I noticed the following WARN message:

WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

What might be the issue?

jacek:~/oss/spark
$ ./bin/spark-shell
Spark assembly has been built with Hive, including Datanucleus jars on classpath
14/05/09 21:11:17 INFO SecurityManager: Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
14/05/09 21:11:17 INFO SecurityManager: Changing view acls to: jacek
14/05/09 21:11:17 INFO SecurityManager: SecurityManager: authentication disabled; ui acls disabled; users with view permissions: Set(jacek)
14/05/09 21:11:17 INFO HttpServer: Starting HTTP Server
Welcome to
      ____              __
     / __/__  ___ _____/ /__
    _\ \/ _ \/ _ `/ __/  '_/
   /___/ .__/\_,_/_/ /_/\_\   version 1.0.0-SNAPSHOT
      /_/

Using Scala version 2.10.4 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0)
Type in expressions to have them evaluated.
Type :help for more information.
...
14/05/09 21:11:49 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
...

Answer 1

Supported Platforms of the Native Libraries Guide documentation in Apache Hadoop reads:

The native hadoop library is supported on *nix platforms only. The library does not to work with Cygwin or the Mac OS X platform.

The native hadoop library is mainly used on the GNU/Linus platform and has been tested on these distributions:

• RHEL4/Fedora
• Ubuntu
• Gentoo

On all the above distributions a 32/64 bit native hadoop library will work with a respective 32/64 bit jvm.

It appears that the WARN message should be disregarded on Mac OS X as the native library doesn't simply exist for the platform.

Answer 2

In my experience, if you cd into the /sparkDir/conf and rename the spark-env.sh.template to spark-env.sh, and then set the JAVA_OPTSand hadoop_DIR, it works.

You will also have to edit this /etc/profile line:

export LD_LIBRARY_PATH=$HADOOP_HOME/lib/native/:$LD_LIBRARY_PATH