anchor.diff:  OLAP traversals with Spark on Yarn
   ----------------------------------
   
  -Tinkerpop's combination of http://tinkerpop.apache.org/docs/current/reference/#sparkgraphcomputer[SparkGraphComputer]
  +TinkerPop's combination of http://tinkerpop.apache.org/docs/current/reference/#sparkgraphcomputer[SparkGraphComputer]
   and http://tinkerpop.apache.org/docs/current/reference/#_properties_files[HadoopGraph] allows for running
   distributed, analytical graph queries (OLAP) on a computer cluster. The
   http://tinkerpop.apache.org/docs/current/reference/#sparkgraphcomputer[reference documentation] covers the cases
  
positive.code: Approach
  ~~~~~~~~
  
  Most configuration problems of Tinkerpop with Spark on Yarn stem from three reasons:
  
  1. `SparkGraphComputer` creates its own `SparkContext` so it does not get any configs from the usual `spark-submit` command.
  2. The Tinkerpop Spark-plugin did not include Spark Yarn runtime dependencies until version 3.2.7/3.3.1.
  3. Resolving reason 2 by adding the cluster's Spark jars to the classpath may create all kinds of version
  conflicts with the Tinkerpop dependencies.
  
  The current recipe follows a minimalist approach in which no dependencies are added to the dependencies
  included in the Tinkerpop binary distribution. The Hadoop cluster's Spark installation is completely ignored. This
  approach minimizes the chance of dependency version conflicts.
  
  Prerequisites
  
negative.code: export HADOOP_HOME=/usr/local/lib/hadoop-2.7.2
  export HADOOP_CONF_DIR=/usr/local/lib/hadoop-2.7.2/etc/hadoop
  
  # Have TinkerPop find the hadoop cluster configs and hadoop native libraries
  export CLASSPATH=$HADOOP_CONF_DIR
  export JAVA_OPTIONS="-Djava.library.path=$HADOOP_HOME/lib/native:$HADOOP_HOME/lib/native/Linux-amd64-64"
  
  