1. 程式人生 > >spark-core_04: org.apache.spark.deploy.SparkSubmit原始碼分析:

spark-core_04: org.apache.spark.deploy.SparkSubmit原始碼分析:

SparkSubmitArgumentsParser的父類就SparkSubmitOptionParser,在launcher.Main方法執行時用到OptionParser 它的父類也是SparkSubmitOptionParser。並且這個父類有一個方法parser。作用將spark-submit放進來的引數對應值賦到spark對應的變數中,如 --class的值 放到mainClass變數中此處在SparkSubmitArguments初始化時也呼叫這個父類的parser方法。

object SparkSubmit {
 
。。。

private[spark] def printVersionAndExit

(): Unit= {
   
printStream.println("""Welcometo
      ____              __
     / __/__  ___ _____/ /__
    _\ \/ _ \/ _ `/ __/  '_/
   /___/ .__/\_,_/_/ /_/\_\   version %s
      /_/
                       """
.format(SPARK_VERSION))
   
printStream.println("Type --helpfor more information.")
   
exitFn(0)
  }
 
// scalastyle:on println

 
def main(args: Array[String]): Unit = {
   
/** 使用SparkSubmitArguments封裝spark-submit傳入的引數:
      * 這是spark-shell傳進來的:“org.apache.spark.deploy.SparkSubmit”
      * --class org.apache.spark.repl.Main --name "Spark shell"--master spark://luyl152:7077,luyl153:7077,luyl154:7077
      * 這是自己的應用通過spark-submit傳進來的:
      * --master spark://luyl152:7077,luyl153:7077,luyl154:7077 --classdt.scala.App /tool/jarDir/maven_scala-1.0-SNAPSHOT.jar
      */

   
val appArgs = new SparkSubmitArguments(args)

一、查看一下new SparkSubmitArguments(args)中初始化呼叫的parse(args)程式碼

/**
 * Parses and encapsulates arguments fromthe spark-submit script.
 * The env argument is used for testing.
  * sys.env :
會將系統中所有環境變數都取出來
 */
private[deploy] class SparkSubmitArguments(args:Seq[String], env: Map[String, String] = sys.env)
 
extends SparkSubmitArgumentsParser {
 
var master: String = null
  var
deployMode: String = null
  var
executorMemory: String= null
  var
executorCores: String= null
  var
totalExecutorCores: String= null
  var
propertiesFile: String= null
  var
driverMemory: String = null
  var
driverExtraClassPath: String= null
  var
driverExtraLibraryPath: String= null
  var
driverExtraJavaOptions: String= null
  ……
// Set parameters from command line arguments
 
try {
    parse(args.asJava) 
//因為parse()方法引數型別是java的List,所以要轉一下
  }
catch {
   
case e: IllegalArgumentException =>
      SparkSubmit.printErrorAndExit(e.getMessage())
  }

……

===>檢視一下SparkSubmitOptionParser的parse程式碼:

/**
 * Parse a list of spark-submit commandline options.
 *
<p>
 
* See SparkSubmitArguments.scala for a more formal descriptionof available options.
 *
 * @throws IllegalArgumentExceptionIf an error is found during parsing
 
* 引數是這些:--class org.apache.spark.repl.Main --name"Spark shell" --master spark://luyl152:7077.
 * 作用就是將spark-submit放進來的引數對應值賦到spark對應的變數中,如 --class的值 放到mainClass變數中

 */
protected finalvoid parse(List<String> args) {
 
//spark-submit可以傳sparkConf引數:--confPROP=VALUE ,引數可以看org.apache.spark.deploy.SparkSubmitArguments類最後面
  //或spark-submit-h就可以檢視
Pattern eqSeparatedOpt = Pattern.compile("(--[^=]+)=(.+)");

  int
idx = 0;
  for
(idx = 0; idx < args.size(); idx++) {
    String arg = args.get(idx)
;
   
String value = null;
   
//當出現--conf PROP=VALUE這種型別的引數arg、value值變成if程式碼裡面的值
Matcher m = eqSeparatedOpt.matcher(arg);
    if
(m.matches()) {
      arg = m.group(
1); //--conf PROP
value = m.group(2); //VALUE
}

   
// Look for options with a value.
   //該方法主要是找到spark-submit後面的帶有--引數,如args 放進"--class",和opts二維陣列進行匹配
    //匹配到的還是返回--class,如果沒有匹配到則null
String name = findCliOption(arg, opts);
    if
(name != null) {
     
if (value== null) {
       
if (idx== args.size() - 1) { //如果匹配了並且沒有引數值則報錯,如:只有 --class ,則size是1,idx此時0, 1-1=0
throw new IllegalArgumentException(
              String.format(
"Missing argument for option'%s'.", arg));
       
}
        idx++
;
       
value = args.get(idx); //如果有值,則idx索引的下一位就是引數對應的值
}
     
//name就是spark-submit的引數如--class,而value就是引數對應的值
      //在它的自身OptionParser做的實現,作用就是將spark-submit放進來的引數對應值賦到spark對應的變數中
      //如 --class的值放到mainClass變數中(裡面實現很easy,就不寫了)

if (!handle(name, value)) {
       
break;
     
}
     
continue; //只有匹配到才會讓idx再次加1
}

  
 // Look for aswitch. 如果上面沒有匹配到,會再去匹配一下是否有出現-verbose這樣引數
name = findCliOption(arg, switches);
    if
(name != null) {
     
if (!handle(name, null)) {
       
break;
     
}
     
continue;
   
}

   
if (!handleUnknown(arg)){
     
break;
   
}
  }

 
if (idx< args.size()) {
    idx++
;
 
}
 
 // 將多出來的引數加到 SparkSubmitCommandBuilder() {his.sparkArgs = new ArrayList<String>();..}
handleExtraArgs(args.subList(idx, args.size()));
}

===》上面handle(name,value)在OptionParser的實現如下

/**
 *作用就是將spark-submit放進來的引數對應值賦到spark對應的變數中
   */

@Override
protected boolean handle(String opt, String value) {
 
if (opt.equals(MASTER)) {
   
master =value;
 
} elseif (opt.equals(DEPLOY_MODE)) {
   
deployMode =value;
 
} elseif (opt.equals(PROPERTIES_FILE)) {
   
propertiesFile = value;
 
} elseif (opt.equals(DRIVER_MEMORY)) {
   
conf.put(SparkLauncher.DRIVER_MEMORY, value);
 
} elseif (opt.equals(DRIVER_JAVA_OPTIONS)) {
   
conf.put(SparkLauncher.DRIVER_EXTRA_JAVA_OPTIONS, value);
 
} elseif (opt.equals(DRIVER_LIBRARY_PATH)) {
   
conf.put(SparkLauncher.DRIVER_EXTRA_LIBRARY_PATH, value);。。。。。

===》初始化new SparkSubmitArguments(args)之後再次返回SparkSubmit$.main方法

//這個verbose只要在spark提交的時候加入:--verbose引數就可以變成true,可以看原始碼實現很easy (可以得到很多資訊如:)
//./spark-submit --classdt.spark.DriverInWinDebuggerCluster --master spark://luyl152:7077,luyl153:7077,luyl154:7077  --verbose /tool/maven_scala-1.0-SNAPSHOT.jar
if (appArgs.verbose) {
     
// scalastyle:off println
     
printStream.println(appArgs)

/**
      * Main class:
        dt.spark.DriverInWinDebuggerCluster
       Arguments:
        System properties:
        spark.yarn.historyServer.address-> luyl152:18080
        spark.eventLog.enabled -> true
        SPARK_SUBMIT -> true
        spark.executor.extraJavaOptions-> -XX:+PrintGCDetails -Dkey=value -Dnumbers="one two three"
        spark.history.fs.logDirectory-> hdfs://ns1/historyserverforspark
        spark.app.name ->dt.spark.DriverInWinDebuggerCluster
        spark.jars ->file:/tool/maven_scala-1.0-SNAPSHOT.jar
        spark.submit.deployMode ->client  #
預設就是client ,在這個類中搜索--deploy-mode,有相關的解釋
        spark.eventLog.dir ->hdfs://ns1/historyserverforspark
        spark.master ->spark://luyl152:7077,luyl153:7077,luyl154:7077
        Classpath elements:
       file:/tool/maven_scala-1.0-SNAPSHOT.jar
      */

      // scalastyle:on println
    }
   /**
這裡的action就是spark-submit執行的動作,包括:SUBMIT, KILL, REQUEST_STATUS(使
      * 用了SparkSubmitAction進行了封裝),如果沒有指定,SparkSubmitArguments設定的值是SparkSubmitAction.SUBMIT,
      * 所以下面的這個模式匹配將執行submit(appArgs)

      */
appArgs.actionmatch {
     
case SparkSubmitAction.SUBMIT => submit(appArgs)
     
case SparkSubmitAction.KILL => kill(appArgs)
     
case SparkSubmitAction.REQUEST_STATUS => requestStatus(appArgs)
    }
  }

二、進入submit(appArgs)分析一下:

/**
 * Submit the application using theprovided parameters.
 *
 * This runs in two steps. First, weprepare the launch environment by setting up
 * the appropriate classpath, systemproperties, and application arguments for
 * running the child main class based onthe cluster manager and the deploy mode.
 * Second, we use this launch environmentto invoke the main method of the child
 * main class.
  *
  * submit
方法的主要功能就是使用傳進來的引數來提交應用程式。
 
* 主要分為兩步驟:
  * 1. 準備啟動所需的環境,包括設定classpath、系統引數和應用程式的引數(根據部署模式和cluster
  * manager執行childmain類)。
  * 2. 使用上一步準備好的環境呼叫child main class中的main函式,我們這裡只考慮client模式,
  * cluster模式我們以後會單獨分析。
  * 所以如果是spark-shell,child main class就是org.apache.spark.repl.Main,如果是
  * spark-submit直接進行提交,child main class就是使用者編寫的應用程式(含有main方法的類)
 */

private def submit(args: SparkSubmitArguments): Unit = {
//childArgs:表示執行主類的main引數是個ArrayBuffer,childClasspath:是主類的jar:/tool/jarDir/maven_scala-1.0-SNAPSHOT.jar
  //sysProps:sparkConf相關的屬性值是個Map, childMainClass就是主類的類全路徑:dt.scala.App
val (childArgs, childClasspath, sysProps, childMainClass)= prepareSubmitEnvironment(args)

1、先分析一下如何prepareSubmitEnvironment(args)方法:

===》這個方法老長了,只分析一下,當前場景對應的程式碼

private[deploy] def prepareSubmitEnvironment(args: SparkSubmitArguments)
    : (
Seq[String], Seq[String], Map[String, String], String) = {
 
// Return values
 
val childArgs= new ArrayBuffer[String]()
 
val childClasspath= new ArrayBuffer[String]()
 
val sysProps= new HashMap[String, String]()
 
var childMainClass= ""

 // Set the cluster manager,master就是spark://luyl152:7077,luyl153:7077,luyl154:7077
val clusterManager: Int = args.mastermatch {
   
case m if m.startsWith("yarn") => YARN
   
case m if m.startsWith("spark")=> STANDALONE
   
case m if m.startsWith("mesos")=> MESOS
   
case m if m.startsWith("local")=> LOCAL
   
case _=> printErrorAndExit("Mastermust start with yarn, spark, mesos, or local"); -1
 
}

// Set the deploy mode; default is client mode:預設是args.deployMode是null,deployMode則是CLIENT的值var deployMode:Int = args.deployModematch {
   
case "client"| null =>CLIENT
   
case "cluster"=> CLUSTER
   
case _=> printErrorAndExit("Deploymode must be either client or cluster"); -1
 
}
…yarn、Mesos、R等相關的程式碼,後面研究到了,再看

  // Update args.deployMode if it is null. It will bepassed down as a Spark property later.
  //由於deployMode是null,deployMode則是CLIENT的值,由會給args.deployMode的值設定client
(args.deployMode, deployMode) match {
   
case (null, CLIENT) => args.deployMode = "client"
   
case (null, CLUSTER) => args.deployMode = "cluster"
   
case _=>
  }

。。。。
  
// Special flag to avoid deprecation warnings at theclient
 
sysProps("SPARK_SUBMIT") = "true"

 
// A list of rules to map each argument to systemproperties or command-line options in
  // each deploy mode; we iterate throughthese below
 
val options= List[OptionAssigner](

   
// All cluster managers
   
OptionAssigner(args.master, ALL_CLUSTER_MGRS, ALL_DEPLOY_MODES, sysProp = "spark.master"),
   
OptionAssigner(args.deployMode, ALL_CLUSTER_MGRS, ALL_DEPLOY_MODES,
     
sysProp = "spark.submit.deployMode"),
   
OptionAssigner(args.name, ALL_CLUSTER_MGRS, ALL_DEPLOY_MODES, sysProp = "spark.app.name"),
   
OptionAssigner(args.jars, ALL_CLUSTER_MGRS, CLIENT, sysProp = "spark.jars"),
   
OptionAssigner(args.ivyRepoPath, ALL_CLUSTER_MGRS, CLIENT, sysProp = "spark.jars.ivy"),
   
OptionAssigner(args.driverMemory, ALL_CLUSTER_MGRS, CLIENT,
     
sysProp = "spark.driver.memory"),
   
OptionAssigner(args.driverExtraClassPath, ALL_CLUSTER_MGRS, ALL_DEPLOY_MODES,
     
sysProp = "spark.driver.extraClassPath"),
   
OptionAssigner(args.driverExtraJavaOptions, ALL_CLUSTER_MGRS, ALL_DEPLOY_MODES,
     
sysProp = "spark.driver.extraJavaOptions"),
   
OptionAssigner(args.driverExtraLibraryPath, ALL_CLUSTER_MGRS, ALL_DEPLOY_MODES,
     
sysProp = "spark.driver.extraLibraryPath"),

   
// Yarn client only
   
。。。。// Other options
   
OptionAssigner(args.executorCores, STANDALONE | YARN, ALL_DEPLOY_MODES,
     
sysProp = "spark.executor.cores"),
   
OptionAssigner(args.executorMemory, STANDALONE | MESOS | YARN, ALL_DEPLOY_MODES,
     
sysProp = "spark.executor.memory"),
   
OptionAssigner(args.totalExecutorCores, STANDALONE | MESOS, ALL_DEPLOY_MODES,
     
sysProp = "spark.cores.max"),
   
OptionAssigner(args.files, LOCAL | STANDALONE | MESOS, ALL_DEPLOY_MODES,
     
sysProp = "spark.files"),
   
OptionAssigner(args.jars, STANDALONE | MESOS, CLUSTER, sysProp = "spark.jars"),
   
OptionAssigner(args.driverMemory, STANDALONE | MESOS, CLUSTER,
     
sysProp = "spark.driver.memory"),
   
OptionAssigner(args.driverCores, STANDALONE | MESOS, CLUSTER,
     
sysProp = "spark.driver.cores"),
   
OptionAssigner(args.supervise.toString, STANDALONE| MESOS, CLUSTER,
     
sysProp = "spark.driver.supervise"),
   
OptionAssigner(args.ivyRepoPath, STANDALONE, CLUSTER, sysProp = "spark.jars.ivy")
  )

 
// In client mode, launch the application main classdirectly
  // In addition, add the mainapplication jar and any added jars (if any) to the classpath
 
if (deployMode== CLIENT) {
    childMainClass = args.
mainClass 

//就是自的main類路徑
//primaryResource就是指定的自已傳進去jar:/tool/jarDir/maven_scala-1.0-SNAPSHOT.jar
if (isUserJar(args.primaryResource)) {
      childClasspath += args.
primaryResource
   
}
   
//是否加第三方--jars
if (args.jars != null) { childClasspath ++= args.jars.split(",") }
   
if (args.childArgs != null) { childArgs ++= args.childArgs }
  }

 
。。。

//Add the application jar automatically so the user doesn't have to callsc.addJar
  // For YARN cluster mode, the jar isalready distributed on each node as "app.jar"
  // For python and R files, the primaryresource is already distributed as a regular file
  /
/當不是yarn,也不python也不是r的時候會進入這個語句
  if (!isYarnCluster&& !args.isPython && !args.isR) {
   
var jars= sysProps.get("spark.jars").map(x => x.split(",").toSeq).getOrElse(Seq.empty)
   
if (isUserJar(args.primaryResource)) {
      jars = jars ++
Seq(args.primaryResource)
    }
   
//將 第三方--jars放在spark.jars中,按逗號分開
    sysProps.put("spark.jars", jars.mkString(","))
  }
。。。
 
// Load any properties specified through --conf and thedefault properties file
for ((k, v) <- args.sparkProperties) {
    sysProps.getOrElseUpdate(k
, v)
  }
 
。。。。
 
// Resolve paths in certain spark properties
 
val pathConfigs= Seq(
   
"spark.jars",
   
"spark.files",
   
"spark.yarn.jar",
   
"spark.yarn.dist.files",
   
"spark.yarn.dist.archives")
  pathConfigs.foreach { config =>
   
// Replace old URIs with resolved URIs, if they exist
   
sysProps.get(config).foreach { oldValue =>
      sysProps(config) = Utils.resolveURIs(oldValue)
    }
  }
。。。。。
  (childArgs
, childClasspath, sysProps, childMainClass)
}

===》執行完成之後,(會將--class對應的引數,--class對應的jar包,sysProps屬性,--class的類全路徑)放到元組中返回。

三、接著回到submit(appArgs)方法中

//這個doRunMain()會被它下面程式碼進行呼叫def doRunMain(): Unit = {
   
if (args.proxyUser != null) {
    
 // spark-submit可以指定liunx的使用者, 在提交時指定--proxy-user的值,否則arg.proxyUser是為空
val proxyUser= UserGroupInformation.createProxyUser(args.proxyUser,
       
UserGroupInformation.getCurrentUser())
     
try {
        proxyUser.doAs(
new PrivilegedExceptionAction[Unit](){
         
override def run(): Unit = {
            runMain(childArgs
, childClasspath, sysProps, childMainClass, args.verbose)
          }
        })
      }
catch {
       
case e: Exception =>
         
// Hadoop's AuthorizationException suppresses theexception's stack trace, which
          // makes the message printed tothe output by the JVM not very helpful. Instead,
          // detect exceptions with emptystack traces here, and treat them differently.
         
if (e.getStackTrace().length== 0) {
           
// scalastyle:off println
           
printStream.println(s"ERROR: ${e.getClass().getName()}: ${e.getMessage()}")
           
// scalastyle:on println
           
exitFn(1)
          }
else {
           
throw e
          }
      }
    }
else {
      runMain(childArgs
, childClasspath, sysProps, childMainClass, args.verbose)
    }
  }
 
 // In standalonecluster mode, there are two submission gateways:
   //  (1) The traditional Akka gateway using o.a.s.deploy.Client as a wrapper
   //  (2) The new REST-based gateway introduced in Spark 1.3
   // The latter is the default behavioras of Spark 1.3, but Spark submit will fail over
   // to use the legacy gateway if themaster endpoint turns out to be not a REST server.

 //在獨立群集模式下,有兩個提交閘道器:
 
// (1)使用o.a.s.deploy.Client作為包裝的傳統Akka閘道器
  // (2)Spark 1.3中引入的基於REST的新閘道器,後者是Spark 1.3的預設行為,但如果主端點不是REST伺服器,則Spark提交將故障轉移到使用傳統閘道器。

  /** http://spark.apache.org/docs/latest/submitting-applications.html
    *http://blog.csdn.net/Trigl/article/details/72732241
    * 1,standalone 執行apark-submit時,不設定--deploy-mode,它的值就是client。該模式的場景:client需要和master在同一個網段上
    * 因為Drive要和Executorr通訊,例如Drive需要將Jar包通過NettyHTTP分發到Executor,Driver要給Executor分配任務等
    * a,執行spark-submit指令碼稱為master,執行自已寫的main方法是driver,在client中driver和master是在一個節點。
    * b,Driver也是一個executer,稱為第三方client,Driver程序不在Worker節點上,所以其是獨立的,不會消耗Worker叢集的資源
    * c,client模式中沒有監督重啟機制(即設定了–supervise沒有用),Driver程序如果掛了,需要額外的程式重啟。
    *
    * 2,如果在提交spark-submit指令碼時,設定--deploy-mode cluster:使用的場景是worker和master不在一個網段中 表示driver會在worker節點中,會佔用worker的資源
    *  a,cluster模式下,可以設定–supervise對Driver進行監控,如果Driver掛了可以自動重啟
    *  b,cluster模式下,worker和master一般不在一個網段,所以各個jar提前放到worker節點中
    *  c,Driver類即自己的main類,分配在哪個點中是由master來分配的
    */
  // master.startsWith("spark://")&& deployMode == "cluster" deployMode 預設是 client。useRest預設是true
if (args.isStandaloneCluster&& args.useRest) {
   
try {
     
// scalastyle:off println
     
printStream.println("Running Sparkusing the REST application submission protocol.")
     
// scalastyle:on println
     
doRunMain()
    }
catch {
     
// Fail over to use the legacy submission gateway
     
case e:SubmitRestConnectionException =>
        printWarning(
s"Master endpoint ${args.master} was not a REST server. " +
         
"Falling back to legacy submission gatewayinstead.")
        args.
useRest = false
       
submit(args)
    }
 
// In all other modes, just run the main class as prepared
 
} else{
    doRunMain()
  }
}

四,進入runMain(childArgs, childClasspath, sysProps, childMainClass,args.verbose)程式碼實現:

* childArgs:表示執行主類的main的引數是個ArrayBuffer,childClasspath:是主類的jar:/tool/jarDir/maven_scala-1.0-SNAPSHOT.jar
    sysProps:sparkConf相關的屬性值是個Map(解析SparkSubmit.prepareSubmitEnvironment()得到的資料), childMainClass就是主類的類全路徑:dt.scala.App
 */

private def runMain(
    childArgs:
Seq[String],
   
childClasspath: Seq[String],
   
sysProps: Map[String, String],
   
childMainClass: String,
   
verbose: Boolean): Unit = {
 
// scalastyle:off println
 
 //這個verbose只要在spark提交的時候加入:--verbose引數就可以變成true,可以看原始碼實現很easyif (verbose){
   
printStream.println(s"Main class:\n$childMainClass")
   
printStream.println(s"Arguments:\n${childArgs.mkString("\n")}")
   
printStream.println(s"Systemproperties:\n${sysProps.mkString("\n")}")
   
printStream.println(s"Classpathelements:\n${childClasspath.mkString("\n")}")
   
printStream.println("\n")
  }
 
// scalastyle:on println
  //繼承URLClassLoader將jar包加到jvm中。會使用MutableURLClassLoader來載入jar包

val loader =