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spark-submit script

spark-submit script allows you to manage your Spark applications. You can submit your Spark application to a Spark deployment environment, kill or request status of Spark applications.

You can find spark-submit script in bin directory of the Spark distribution.

$ ./bin/spark-submit
Usage: spark-submit [options] <app jar | python file> [app arguments]
Usage: spark-submit --kill [submission ID] --master [spark://...]
Usage: spark-submit --status [submission ID] --master [spark://...]
Usage: spark-submit run-example [options] example-class [example args]
...

Driver Cores in Cluster Deploy Mode (--driver-cores option)

--driver-cores NUM

--driver-cores command-line option sets the number of cores for the driver in the cluster deploy mode.

Note
 --driver-cores switch is only available for cluster mode (for Standalone, Mesos, and YARN).
Note
 It corresponds to spark.driver.cores setting.
Note
 It is printed out to the standard error output in verbose mode.

System Properties

spark-submit collects system properties for execution in the internal sysProps.

Caution
 FIXME How is sysProps calculated?

Additional JAR Files to Distribute (--jars option)

--jars JARS

--jars is a comma-separated list of local jars to include on the driver’s and executors' classpaths.

Caution
 FIXME

Additional Files to Distribute (--files option)

--files FILES
Caution
 FIXME

Additional Archives to Distribute (--archives option)

--archives ARCHIVES
Caution
 FIXME

Specifying YARN Resource Queue (--queue option)

--queue QUEUE_NAME

With --queue you can choose the YARN resource queue to submit a Spark application to. The default queue name is default.

Caution
 FIXME What is a queue?
Note
 It corresponds to spark.yarn.queue Spark’s setting.
Tip
 It is printed out to the standard error output in verbose mode.

Actions

Submitting Applications for Execution (submit method)

The default action of spark-submit script is to submit a Spark application to a deployment environment for execution.

Tip
 Use --verbose command-line switch to know the main class to be executed, arguments, system properties, and classpath (to ensure that the command-line arguments and switches were processed properly).

When executed, spark-submit executes submit method.

submit(args: SparkSubmitArguments): Unit

If proxyUser is set it will…​FIXME

Caution
 FIXME Review why and when to use proxyUser.

It passes the execution on to runMain.

Executing Main (runMain method)
runMain(
  childArgs: Seq[String],
  childClasspath: Seq[String],
  sysProps: Map[String, String],
  childMainClass: String,
  verbose: Boolean): Unit

runMain is an internal method to build execution environment and invoke the main method of the Spark application that has been submitted for execution.

Note
 It is exclusively used when submitting applications for execution.

It optionally prints out input parameters with verbose input flag enabled (i.e. true).

Note
 verbose flag corresponds to --verbose switch.

It builds the context classloader depending on spark.driver.userClassPathFirst flag.

Caution
 FIXME What is spark.driver.userClassPathFirst?

It adds the local jars specified in childClasspath input parameter to the context classloader (that is later responsible for loading the childMainClass main class).

Note
 childClasspath input parameter corresponds to --jars switch with the primary resource if specified in client deploy mode.

It sets all the system properties specified in sysProps input parameter.

Note
 It uses Java’s System.setProperty to set the system properties.
Tip
 Read System Properties about how the process of collecting system properties works.

It creates an instance of childMainClass main class.

Note
 childMainClass corresponds to the main class spark-submit was invoked with.
Tip
 You should avoid using scala.App trait for main classes in Scala as reported in SPARK-4170 Closure problems when running Scala app that "extends App"

If you use scala.App for the main class, you should see the following WARN message in the logs:

WARN Subclasses of scala.App may not work correctly. Use a main() method instead.

Finally, it executes the main method of the Spark application passing in the childArgs arguments.

Any SparkUserAppException exceptions lead to System.exit while the others are simply re-thrown.

Adding Local Jars to ClassLoader (addJarToClasspath method)
addJarToClasspath(localJar: String, loader: MutableURLClassLoader)

addJarToClasspath is an internal method to add file or local jars (as localJar) to the loader classloader.

Internally, addJarToClasspath resolves the URI of localJar. If the URI is file or local and the file denoted by localJar exists, localJar is added to loader. Otherwise, the following warning is printed out to the logs:

Warning: Local jar /path/to/fake.jar does not exist, skipping.

For all other URIs, the following warning is printed out to the logs:

Warning: Skip remote jar hdfs://fake.jar.
Note
 addJarToClasspath assumes file URI when localJar has no URI specified, e.g. /path/to/local.jar.
Caution
 FIXME What is a URI fragment? How does this change re YARN distributed cache? See Utils#resolveURI.

Killing Applications (--kill switch)

--kill

Requesting Application Status (--status switch)

--status

Command-line Options

Execute spark-submit --help to know about the command-line options supported.

➜  spark git:(master) ✗ ./bin/spark-submit --help
Usage: spark-submit [options] <app jar | python file> [app arguments]
Usage: spark-submit --kill [submission ID] --master [spark://...]
Usage: spark-submit --status [submission ID] --master [spark://...]
Usage: spark-submit run-example [options] example-class [example args]

Options:
  --master MASTER_URL         spark://host:port, mesos://host:port, yarn, or local.
  --deploy-mode DEPLOY_MODE   Whether to launch the driver program locally ("client") or
                              on one of the worker machines inside the cluster ("cluster")
                              (Default: client).
  --class CLASS_NAME          Your application's main class (for Java / Scala apps).
  --name NAME                 A name of your application.
  --jars JARS                 Comma-separated list of local jars to include on the driver
                              and executor classpaths.
  --packages                  Comma-separated list of maven coordinates of jars to include
                              on the driver and executor classpaths. Will search the local
                              maven repo, then maven central and any additional remote
                              repositories given by --repositories. The format for the
                              coordinates should be groupId:artifactId:version.
  --exclude-packages          Comma-separated list of groupId:artifactId, to exclude while
                              resolving the dependencies provided in --packages to avoid
                              dependency conflicts.
  --repositories              Comma-separated list of additional remote repositories to
                              search for the maven coordinates given with --packages.
  --py-files PY_FILES         Comma-separated list of .zip, .egg, or .py files to place
                              on the PYTHONPATH for Python apps.
  --files FILES               Comma-separated list of files to be placed in the working
                              directory of each executor.

  --conf PROP=VALUE           Arbitrary Spark configuration property.
  --properties-file FILE      Path to a file from which to load extra properties. If not
                              specified, this will look for conf/spark-defaults.conf.

  --driver-memory MEM         Memory for driver (e.g. 1000M, 2G) (Default: 1024M).
  --driver-java-options       Extra Java options to pass to the driver.
  --driver-library-path       Extra library path entries to pass to the driver.
  --driver-class-path         Extra class path entries to pass to the driver. Note that
                              jars added with --jars are automatically included in the
                              classpath.

  --executor-memory MEM       Memory per executor (e.g. 1000M, 2G) (Default: 1G).

  --proxy-user NAME           User to impersonate when submitting the application.
                              This argument does not work with --principal / --keytab.

  --help, -h                  Show this help message and exit.
  --verbose, -v               Print additional debug output.
  --version,                  Print the version of current Spark.

 Spark standalone with cluster deploy mode only:
  --driver-cores NUM          Cores for driver (Default: 1).

 Spark standalone or Mesos with cluster deploy mode only:
  --supervise                 If given, restarts the driver on failure.
  --kill SUBMISSION_ID        If given, kills the driver specified.
  --status SUBMISSION_ID      If given, requests the status of the driver specified.

 Spark standalone and Mesos only:
  --total-executor-cores NUM  Total cores for all executors.

 Spark standalone and YARN only:
  --executor-cores NUM        Number of cores per executor. (Default: 1 in YARN mode,
                              or all available cores on the worker in standalone mode)

 YARN-only:
  --driver-cores NUM          Number of cores used by the driver, only in cluster mode
                              (Default: 1).
  --queue QUEUE_NAME          The YARN queue to submit to (Default: "default").
  --num-executors NUM         Number of executors to launch (Default: 2).
  --archives ARCHIVES         Comma separated list of archives to be extracted into the
                              working directory of each executor.
  --principal PRINCIPAL       Principal to be used to login to KDC, while running on
                              secure HDFS.
  --keytab KEYTAB             The full path to the file that contains the keytab for the
                              principal specified above. This keytab will be copied to
                              the node running the Application Master via the Secure
                              Distributed Cache, for renewing the login tickets and the
                              delegation tokens periodically.

List of switches, i.e. command-line options that do not take parameters:

YARN-only options:

Version (--version switch)

$ ./bin/spark-submit --version
Welcome to
      ____              __
     / __/__  ___ _____/ /__
    _\ \/ _ \/ _ `/ __/  '_/
   /___/ .__/\_,_/_/ /_/\_\   version 2.0.0-SNAPSHOT
      /_/

Type --help for more information.

Verbose Mode (--verbose switch)

When spark-submit is executed with --verbose command-line switch, it enters verbose mode.

In verbose mode, the parsed arguments are printed out to the System error output.

FIXME

It also prints out propertiesFile and the properties from the file.

FIXME

Deploy Mode (--deploy-mode switch)

You use spark-submit’s --deploy-mode command-line option to specify the deploy mode for a Spark application.

Environment Variables

The following is the list of environment variables that are considered when command-line options are not specified:

  • MASTER for --master

  • SPARK_DRIVER_MEMORY for --driver-memory

  • SPARK_EXECUTOR_MEMORY (see Environment Variables in the SparkContext document)

  • SPARK_EXECUTOR_CORES

  • DEPLOY_MODE

  • SPARK_YARN_APP_NAME

  • _SPARK_CMD_USAGE

External packages and custom repositories

The spark-submit utility supports specifying external packages using Maven coordinates using --packages and custom repositories using --repositories.

./bin/spark-submit \
  --packages my:awesome:package \
  --repositories s3n://$aws_ak:$aws_sak@bucket/path/to/repo

FIXME Why should I care?

Launching SparkSubmit (main method)

Note

Set SPARK_PRINT_LAUNCH_COMMAND to see the final command to be executed, e.g.

SPARK_PRINT_LAUNCH_COMMAND=1 ./bin/spark-shell
Tip
 The source code of the script lives in https://github.com/apache/spark/blob/master/bin/spark-submit.

When executed, spark-submit script simply passes the call to spark-class with org.apache.spark.deploy.SparkSubmit class followed by command-line arguments.

It creates an instance of SparkSubmitArguments.

If in verbose mode, it prints out the application arguments.

It then relays the execution to action-specific internal methods (with the application arguments):

  • When no action was explicitly given, it is assumed submit action.

  • kill (when --kill switch is used)

  • requestStatus (when --status switch is used)

Note
 The action can only have one of the three available values: SUBMIT, KILL, or REQUEST_STATUS.

SparkSubmitArguments — spark-submit Command-Line Argument Parser

SparkSubmitArguments is a private[deploy] class to handle the command-line arguments of spark-submit script that the actions use for their execution (possibly with the explicit env environment).

SparkSubmitArguments(
  args: Seq[String],
  env: Map[String, String] = sys.env)
Note
 SparkSubmitArguments is created when launching spark-submit script with only args passed in and later used for printing the arguments in verbose mode.

spark-env.sh - load additional environment settings

  • spark-env.sh consists of environment settings to configure Spark for your site.

    export JAVA_HOME=/your/directory/java
export HADOOP_HOME=/usr/lib/hadoop
export SPARK_WORKER_CORES=2
export SPARK_WORKER_MEMORY=1G

  • spark-env.sh is loaded at the startup of Spark’s command line scripts.

  • SPARK_ENV_LOADED env var is to ensure the spark-env.sh script is loaded once.

  • SPARK_CONF_DIR points at the directory with spark-env.sh or $SPARK_HOME/conf is used.

  • spark-env.sh is executed if it exists.

  • $SPARK_HOME/conf directory has spark-env.sh.template file that serves as a template for your own custom configuration.

Consult Environment Variables in the official documentation.