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Spark Submit — spark-submit shell script

Spark Submit — spark-submit shell script

spark-submit shell script allows you to manage your Spark applications.

You can submit your Spark application to a Spark deployment environment for execution, kill or request status of Spark applications.

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

When executed, spark-submit script first checks whether SPARK_HOME environment variable is set and sets it to the directory that contains bin/spark-submit shell script if not. It then executes spark-class shell script to run SparkSubmit standalone application.

Caution
FIXME Add Cluster Manager and Deploy Mode to the table below (see options value)
Table 1. Command-Line Options, Spark Properties and Environment Variables (from SparkSubmitArguments‘s loadEnvironmentArguments and handle)
Command-Line Option Spark Property Environment Variable Description Internal Property

action

Defaults to SUBMIT

--archives

archives

--conf

sparkProperties

--deploy-mode

spark.submit.deployMode

DEPLOY_MODE

Deploy mode

deployMode

--driver-class-path

spark.driver.extraClassPath

The driver’s class path

driverExtraClassPath

--driver-java-options

spark.driver.extraJavaOptions

The driver’s JVM options

driverExtraJavaOptions

--driver-library-path

spark.driver.extraLibraryPath

The driver’s native library path

driverExtraLibraryPath

--driver-memory

spark.driver.memory

SPARK_DRIVER_MEMORY

The driver’s memory

driverMemory

--driver-cores

spark.driver.cores

driverCores

--exclude-packages

spark.jars.excludes

packagesExclusions

--executor-cores

spark.executor.cores

SPARK_EXECUTOR_CORES

The number of executor CPU cores

executorCores

--executor-memory

spark.executor.memory

SPARK_EXECUTOR_MEMORY

An executor’s memory

executorMemory

--files

spark.files

files

ivyRepoPath

spark.jars.ivy

--jars

spark.jars

jars

--keytab

spark.yarn.keytab

keytab

--kill

submissionToKill and action set to KILL

--master

spark.master

MASTER

Master URL. Defaults to local[*]

master

--class

mainClass

--name

spark.app.name

SPARK_YARN_APP_NAME (YARN only)

Uses mainClass or the directory off primaryResource when no other ways set it

name

--num-executors

spark.executor.instances

numExecutors

--packages

spark.jars.packages

packages

--principal

spark.yarn.principal

principal

--properties-file

spark.yarn.principal

propertiesFile

--proxy-user

proxyUser

--py-files

pyFiles

--queue

queue

--repositories

repositories

--status

submissionToRequestStatusFor and action set to REQUEST_STATUS

--supervise

supervise

--total-executor-cores

spark.cores.max

totalExecutorCores

--verbose

verbose

--version

SparkSubmit.printVersionAndExit()

--help

printUsageAndExit(0)

--usage-error

printUsageAndExit(1)

Tip

Set SPARK_PRINT_LAUNCH_COMMAND environment variable to have the complete Spark command printed out to the console, e.g.

Refer to Print Launch Command of Spark Scripts (or org.apache.spark.launcher.Main Standalone Application where this environment variable is actually used).

Tip

Avoid using scala.App trait for a Spark application’s main class in Scala as reported in SPARK-4170 Closure problems when running Scala app that “extends App”.

Preparing Submit Environment — prepareSubmitEnvironment Internal Method

prepareSubmitEnvironment creates a 4-element tuple, i.e. (childArgs, childClasspath, sysProps, childMainClass).

Table 2. prepareSubmitEnvironment‘s Four-Element Return Tuple
Element Description

childArgs

Arguments

childClasspath

Classpath elements

sysProps

Spark properties

childMainClass

Main class

prepareSubmitEnvironment uses options to…​

Caution
FIXME
Note
prepareSubmitEnvironment is used in SparkSubmit object.
Tip
See the elements of the return tuple using --verbose command-line option.

Custom Spark Properties File — --properties-file command-line option

--properties-file command-line option sets the path to a file FILE from which Spark loads extra Spark properties.

Tip
Spark uses conf/spark-defaults.conf by default.

Driver Cores in Cluster Deploy Mode — --driver-cores command-line option

--driver-cores command-line option sets the number of cores to NUM 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.

Additional JAR Files to Distribute — --jars command-line option

--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 command-line option

Caution
FIXME

Additional Archives to Distribute — --archives command-line option

Caution
FIXME

Specifying YARN Resource Queue — --queue command-line option

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.

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 internal method

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.

When verbose input flag is enabled (i.e. true) runMain prints out all the input parameters, i.e. childMainClass, childArgs, sysProps, and childClasspath (in that order).

Note
Use spark-submit‘s –verbose command-line option to enable verbose flag.

runMain builds the context classloader (as loader) depending on spark.driver.userClassPathFirst flag.

Caution
FIXME Describe spark.driver.userClassPathFirst

It adds the 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 command-line option with the primary resource if specified in client deploy mode.

It sets all the system properties specified in sysProps input parameter (using Java’s System.setProperty method).

It creates an instance of childMainClass main class (as mainClass).

Note
childMainClass is the main class spark-submit has been invoked with.
Tip
Avoid using scala.App trait for a Spark application’s main class 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 warning message in the logs:

Finally, runMain 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 internal method

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:

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

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 command-line option

--kill

Requesting Application Status — --status command-line option

--status

Command-line Options

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

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

YARN-only options:

--driver-class-path command-line option

--driver-class-path command-line option sets the extra class path entries (e.g. jars and directories) that should be added to a driver’s JVM.

Tip
You should use --driver-class-path in client deploy mode (not SparkConf) to ensure that the CLASSPATH is set up with the entries. client deploy mode uses the same JVM for the driver as spark-submit‘s.

--driver-class-path sets the internal driverExtraClassPath property (when SparkSubmitArguments.handle called).

It works for all cluster managers and deploy modes.

If driverExtraClassPath not set on command-line, the spark.driver.extraClassPath setting is used.

Note
Command-line options (e.g. --driver-class-path) have higher precedence than their corresponding Spark settings in a Spark properties file (e.g. spark.driver.extraClassPath). You can therefore control the final settings by overriding Spark settings on command line using the command-line options.
Table 3. Spark Settings in Spark Properties File and on Command Line
Setting / System Property Command-Line Option Description

spark.driver.extraClassPath

--driver-class-path

Extra class path entries (e.g. jars and directories) to pass to a driver’s JVM.

Version — --version command-line option

Verbose Mode — --verbose command-line option

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

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

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

Deploy Mode — --deploy-mode command-line option

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.

FIXME Why should I care?

Launching SparkSubmit Standalone Application — main method

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.

Tip

spark-class uses the class name — org.apache.spark.deploy.SparkSubmit — to parse command-line arguments appropriately.

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.

spark-env.sh – load additional environment settings

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

  • 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.

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