3 files changed, 13 insertions, 2 deletions
diff --git a/docs/running-on-yarn.md b/docs/running-on-yarn.md
index 6bada9bdd7..f9525743c8 100644
--- a/docs/running-on-yarn.md
+++ b/docs/running-on-yarn.md
@@ -42,6 +42,12 @@ This will build the shaded (consolidated) jar. Typically something like :
 
 If you want to test out the YARN deployment mode, you can use the current Spark examples. A `spark-examples_{{site.SCALA_VERSION}}-{{site.SPARK_VERSION}}` file can be generated by running `sbt/sbt package`. NOTE: since the documentation you're reading is for Spark version {{site.SPARK_VERSION}}, we are assuming here that you have downloaded Spark {{site.SPARK_VERSION}} or checked it out of source control. If you are using a different version of Spark, the version numbers in the jar generated by the sbt package command will obviously be different.
 
+# Configuration
+
+Most of the configs are the same for Spark on YARN as other deploys. See the Configuration page for more information on those.  These are configs that are specific to SPARK on YARN.
+
+* `SPARK_YARN_USER_ENV`, environment variables to add to the Spark processes launched on YARN. This can be a comma separated list of environment variables. ie SPARK_YARN_USER_ENV="JAVA_HOME=/jdk64,FOO=bar"
+
 # Launching Spark on YARN
 
 Ensure that HADOOP_CONF_DIR or YARN_CONF_DIR points to the directory which contains the (client side) configuration files for the hadoop cluster.
diff --git a/yarn/src/main/scala/spark/deploy/yarn/Client.scala b/yarn/src/main/scala/spark/deploy/yarn/Client.scala
index 9d3860b863..854ff53b09 100644
--- a/yarn/src/main/scala/spark/deploy/yarn/Client.scala
+++ b/yarn/src/main/scala/spark/deploy/yarn/Client.scala
@@ -185,6 +185,8 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
       env("SPARK_YARN_LOG4J_SIZE") =  log4jConfLocalRes.getSize().toString()
     }
 
+    // allow users to specify some environment variables
+    Apps.setEnvFromInputString(env, System.getenv("SPARK_YARN_USER_ENV"))
 
     // Add each SPARK-* key to the environment
     System.getenv().filterKeys(_.startsWith("SPARK")).foreach { case (k,v) => env(k) = v }
@@ -241,7 +243,7 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
     // Command for the ApplicationMaster
     var javaCommand = "java";
     val javaHome = System.getenv("JAVA_HOME")
-    if (javaHome != null && !javaHome.isEmpty()) {
+    if ((javaHome != null && !javaHome.isEmpty()) || env.isDefinedAt("JAVA_HOME")){
       javaCommand = Environment.JAVA_HOME.$() + "/bin/java"
     }
 
diff --git a/yarn/src/main/scala/spark/deploy/yarn/WorkerRunnable.scala b/yarn/src/main/scala/spark/deploy/yarn/WorkerRunnable.scala
index f458f2f6a1..3e007509e6 100644
--- a/yarn/src/main/scala/spark/deploy/yarn/WorkerRunnable.scala
+++ b/yarn/src/main/scala/spark/deploy/yarn/WorkerRunnable.scala
@@ -104,7 +104,7 @@ class WorkerRunnable(container: Container, conf: Configuration, masterAddress: S
 
     var javaCommand = "java";
     val javaHome = System.getenv("JAVA_HOME")
-    if (javaHome != null && !javaHome.isEmpty()) {
+    if ((javaHome != null && !javaHome.isEmpty()) || env.isDefinedAt("JAVA_HOME")) {
       javaCommand = Environment.JAVA_HOME.$() + "/bin/java"
     }
 
@@ -187,6 +187,9 @@ class WorkerRunnable(container: Container, conf: Configuration, masterAddress: S
     Apps.addToEnvironment(env, Environment.CLASSPATH.name, "$CLASSPATH")
     Client.populateHadoopClasspath(yarnConf, env)
 
+    // allow users to specify some environment variables
+    Apps.setEnvFromInputString(env, System.getenv("SPARK_YARN_USER_ENV"))
+
     System.getenv().filterKeys(_.startsWith("SPARK")).foreach { case (k,v) => env(k) = v }
     return env
   }