grinder 进程管理

grinder agent 进程的主入口

class Grinder.java

  public static void main(String[] args) {

    try {
      final Grinder grinder = new Grinder(args, logger);

      //调用grinder的run方法。
      grinder.run();
    }

  private void run() throws GrinderException {

    //调用agent的run
    m_agent.run();

//Agent interface.

interface Agent

  //agent接口的run方法，有2个实现。agentdaemon和agentImpl

  void run() throws GrinderException;

//start agent

public final class AgentDaemon implements Agent

public void run() throws GrinderException {

// 啥意思？google一下
    Runtime.getRuntime().addShutdownHook(m_shutdownHook);

    try {
      while (true) {

//agent.run
        m_delegateAgent.run();

        m_logger.info("agent finished");

        m_sleeper.sleepNormal(m_sleepTime);
      }
    }

class agentImpl

//Run the Grinder agent process.

public void run() throws GrinderException {

        // 最重要的2个参数，script和properties

        ScriptLocation script = null;
        GrinderProperties properties;

        do {
          properties =
            createAndMergeProperties(startMessage != null ?
                                     startMessage.getProperties() : null);

          if (startMessage != null) {
            final GrinderProperties messageProperties =
              startMessage.getProperties();

          if (script == null) {
            final File scriptFile =
              properties.resolveRelativeFile(
                properties.getFile(GrinderProperties.SCRIPT,
                                   GrinderProperties.DEFAULT_SCRIPT));

            script = new ScriptLocation(scriptFile);
          }

            //

            final WorkerProcessCommandLine workerCommandLine =
              new WorkerProcessCommandLine(properties,
                                           System.getProperties(),
                                           jvmArguments,
                                           script.getDirectory());

           // 传入script 和properties参数

            workerFactory =
              new ProcessWorkerFactory(
                workerCommandLine, m_agentIdentity, m_fanOutStreamSender,
                consoleCommunication != null, script, properties);

//

          final WorkerLauncher workerLauncher =
            new WorkerLauncher(properties.getInt("grinder.processes", 1),
                               workerFactory,
                               m_eventSynchronisation,
                               m_logger);

            //启动worker进程

            workerLauncher.startAllWorkers();

//Manages launching a set of workers.

class WorkerLauncher

//启动所有的workers

 public void startAllWorkers() throws EngineException {

//调用startSomeWorkers方法
    startSomeWorkers(m_workers.length - m_nextWorkerIndex);
  }

public boolean startSomeWorkers(int numberOfWorkers)
    throws EngineException {

    final int numberToStart =
      Math.min(numberOfWorkers, m_workers.length - m_nextWorkerIndex);

    for (int i = 0; i < numberToStart; ++i) {
      final int workerIndex = m_nextWorkerIndex;
      //通过workerFactory的create方法，创建worker进程。 
      final Worker worker = m_workerFactory.create(System.out, System.err);

class AbstractWorkerFactory implements WorkerFactory

  public Worker create(
    OutputStream outputStream, OutputStream errorStream)
    throws EngineException {
    //创建一个workerId
    final WorkerIdentityImplementation workerIdentity =
      m_agentIdentity.createWorkerIdentity();

    //传入workerID，out，error参数。创建worker进程

    final Worker worker = createWorker(workerIdentity,
                                       outputStream,
                                       errorStream);

  protected abstract Worker createWorker(
    WorkerIdentityImplementation workerIdentity,
    OutputStream outputStream,
    OutputStream errorStream) throws EngineException;
}

//Class that starts workers as separate processes.

class ProcessWorkerFactory 

  @Override
  protected Worker createWorker(WorkerIdentityImplementation workerIdentity,
                                OutputStream outputStream,
                                OutputStream errorStream)
    throws EngineException {

    return new ProcessWorker(workerIdentity,
                             m_commandLine,
                             outputStream,
                             errorStream);
  }

// This class knows how to start a child process. It redirects the
//child process standard output and error streams to our streams.

class ProcessWorker implements Worker

     private final Process m_process;

     final ProcessBuilder processBuilder =
      new ProcessBuilder(commandLine.getCommandList());

    try {

//通过processBuilder.start。真正启动worker进程。
      m_process = processBuilder.start();
    }

//final class WorkerProcessCommandLine implements CommandLine

  private final List<String> m_command;

  @Override public List<String> getCommandList() {
    return m_command;
  }

  m_command.add(properties.getProperty("grinder.jvm", "java"));

     if (agent != null) {
        try {
          m_command.add("-javaagent:" +
                        workingDirectory.rebaseFile(agent));
        }

         m_command.add(token);

         m_command.add("-classpath");

         m_command.add(workingDirectory.rebasePath(classpath.toString()));

        //worker进程的内部入口。

         m_command.add(WorkerProcessEntryPoint.class.getName());

//Entry point for processes launched by the agent.

//public class WorkerProcessEntryPoint {

 grinderProcess.run();

//class GrinderProcess

  final GrinderProperties properties =
      m_initialisationMessage.getProperties();

    final short numberOfThreads =
      properties.getShort("grinder.threads", (short)1);

    final int duration = properties.getInt("grinder.duration", 0);

    final Instrumenter instrumenter =
      scriptEngineContainer.createInstrumenter();

    final ThreadSynchronisation threadSynchronisation =
      new ThreadSynchronisation(m_eventSynchronisation);

    m_terminalLogger.info("starting threads");
    //同步线程
    synchronized (m_eventSynchronisation) {
      m_threadStarter =
        new ThreadStarterImplementation(threadSynchronisation, scriptEngine);

      for (int i = 0; i < numberOfThreads; i++) {
       //启动线程，执行脚本

        m_threadStarter.startThread(null);
      }
    }
    
    threadSynchronisation.startThreads();