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-rw-r--r-- | docs/configuration.md | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/docs/configuration.md b/docs/configuration.md index 08174878f2..d8317ea97c 100644 --- a/docs/configuration.md +++ b/docs/configuration.md @@ -20,21 +20,21 @@ by running the `conf/spark-env.sh` script in the directory where it is installed in the Git repository, but but you can create it by copying `conf/spark-env.sh.template`. Make sure that you make the copy executable. -Inside `spark-env.sh`, you *must* set at least the following two environment variables: +Inside `spark-env.sh`, you *must* set at least the following two variables: -* `SCALA_HOME` to point to your Scala installation. -* `MESOS_NATIVE_LIBRARY` if you are [running on a Mesos cluster](running-on-mesos.html). +* `SCALA_HOME`, to point to your Scala installation. +* `MESOS_NATIVE_LIBRARY`, if you are [running on a Mesos cluster](running-on-mesos.html). In addition, there are four other variables that control execution. These can be set *either in `spark-env.sh` or in each job's driver program*, because they will automatically be propagated to workers from the driver. For a multi-user environment, we recommend setting the in the driver program instead of `spark-env.sh`, so that different user jobs can use different amounts of memory, JVM options, etc. -* `SPARK_MEM` to set the amount of memory used per node (this should be in the same format as the +* `SPARK_MEM`, to set the amount of memory used per node (this should be in the same format as the JVM's -Xmx option, e.g. `300m` or `1g`) -* `SPARK_JAVA_OPTS` to add JVM options. This includes any system properties that you'd like to pass with `-D`. -* `SPARK_CLASSPATH` to add elements to Spark's classpath. -* `SPARK_LIBRARY_PATH` to add search directories for native libraries. +* `SPARK_JAVA_OPTS`, to add JVM options. This includes any system properties that you'd like to pass with `-D`. +* `SPARK_CLASSPATH`, to add elements to Spark's classpath. +* `SPARK_LIBRARY_PATH`, to add search directories for native libraries. Note that if you do set these in `spark-env.sh`, they will override the values set by user programs, which is undesirable; you can choose to have `spark-env.sh` set them only if the user program hasn't, as follows: |