Pool 类

    (PECL pthreads >= 2.0.0)

    简介

    Pool 对象是多个 Worker 对象的容器，同时也是它们的控制器。

    线程池是对 Worker 功能的高层抽象，包括按照 pthreads 需要的方式来管理应用的功能。

    类摘要

    class Pool {
    /* 属性 */
    protected $size;
    protected $class;
    protected $workers;
    protected $ctor;
    protected $last;
    /* 方法 */
    public __construct(int $size, string $class = ?, array $ctor = ?)
    public collect(Callable $collector = ?): int
    publicresize(int $size): void
    publicshutdown(): void
    public submit(Threaded $task): int
    public submitTo(int $worker, Threaded $task): int
    }

    属性

    size

    Pool 对象可容纳的 Worker 对象的最大数量

    class

    Worker 的类

    workers

    指向 Worker 对象的引用

    ctor

    构造新的 Worker 对象时所需的参数

    last

    最后使用的 Worker 对象在池中的位置偏移量

    目录

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    用户贡献的备注 4 notes

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    4
    meadowsjared at gmail dot com
    3 years ago
    In this example, it shows how to use a pool to get an array of results, using pThreads v3.2.1 and php 7.3.23

    <?php
    class TestWork extends Threaded {
    //updated version that works with pThreads v3.2.1 and php 7.3.23
    protected $complete;
    //$pData is the data sent to your worker thread to do it's job.
    public function __construct($pData) {
    //transfer all the variables to local variables
    $this->complete = false;
    $this->testData = $pData;
    }
    //This is where all of your work will be done.
    public function run() {
    usleep(2000000); //sleep 2 seconds to simulate a large job
    $this->complete = true;
    }
    public function     isDone() {
    return     $this->complete;
    }
    }
    class     ExamplePool extends Pool {
    public     $data = array(); // used to return data after we're done
    private $numTasks = 0; // counter used to know when we're done
    /**
    * override the submit function from the parent
    * to keep track of our jobs
    */
    public function submit(Threaded $task) {
    $this->numTasks++;
    parent::submit($task);
    }
    /**
    * used to wait until all workers are done
    */
    public function process() {
    // Run this loop as long as we have
    // jobs in the pool
    while (count($this->data) < $this->numTasks) {
    $this->collect(function (TestWork $task) {
    // If a task was marked as done, collect its results
    if ($task->isDone()) {
    $tmpObj = new stdclass();
    $tmpObj->complete = $task->complete;
    //this is how you get your completed data back out [accessed by $pool->process()]
    $this->data[] = $tmpObj;
    }
    return     $task->isDone();
    });
    }
    // All jobs are done
    // we can shutdown the pool
    $this->shutdown();
    return     $this->data;
    }
    }
    $pool = new ExamplePool(3);
    $testData = 'asdf';
    for(    $i=0;$i<5;$i++) {
    $pool->submit(new TestWork($testData));
    }
    $retArr = $pool->process(); //get all of the results
    echo '<pre>';
    print_r($retArr); //return the array of results (and maybe errors)
    echo '</pre>';
    ?>
    up
    5
    meadowsjared at gmail dot com
    8 years ago
    Please note, when using the collect function, it's important that you extend the pool class so you can keep checking for finished threads until they're all done.

    <?php
    class TestWork extends Threaded {
    protected     $complete;
    //$pData is the data sent to your worker thread to do it's job.
    public function __construct($pData){
    //transfer all the variables to local variables
    $this->complete = false;
    $this->testData = $pData;
    }
    //This is where all of your work will be done.
    public function run(){
    usleep(2000000); //sleep 2 seconds to simulate a large job
    $this->complete = true;
    }
    public function     isGarbage() {
    return     $this->complete;
    }
    }
    class     ExamplePool extends Pool
    {
    public     $data = array();
    public function     process()
    {
    // Run this loop as long as we have
    // jobs in the pool
    while (count($this->work)) {
    $this->collect(function (TestWork $task) {
    // If a task was marked as done
    // collect its results
    if ($task->isGarbage()) {
    $tmpObj = new stdclass();
    $tmpObj->complete = $task->complete;
    //this is how you get your completed data back out [accessed by $pool->process()]
    $this->data[] = $tmpObj;
    }
    return     $task->isGarbage();
    });
    }
    // All jobs are done
    // we can shutdown the pool
    $this->shutdown();
    return     $this->data;
    }
    }
    $pool = new ExamplePool(3);
    $testData = 'asdf';
    for(    $i=0;$i<5;$i++) {
    $pool->submit(new TestWork($testData));
    }
    $retArr = $pool->process(); //get all of the results
    echo '<pre>';
    print_r($retArr); //return the array of results (and maybe errors)
    echo '</pre>';
    ?>
    up
    2
    olavk
    9 years ago
    Simple example with Collectable (basically Thread meant for Pool) and Pool

    <?php

    class job extends Collectable {
    public     $val;

    public function     __construct($val){
    // init some properties
    $this->val = $val;
    }
    public function     run(){
    // do some work
    $this->val = $this->val . file_get_contents('http://www.example.com/', null, null, 3, 20);
    $this->setGarbage();
    }
    }

    // At most 3 threads will work at once
    $p = new Pool(3);

    $tasks = array(
    new     job('0'),
    new     job('1'),
    new     job('2'),
    new     job('3'),
    new     job('4'),
    new     job('5'),
    new     job('6'),
    new     job('7'),
    new     job('8'),
    new     job('9'),
    new     job('10'),
    );
    // Add tasks to pool queue
    foreach ($tasks as $task) {
    $p->submit($task);
    }

    // shutdown will wait for current queue to be completed
    $p->shutdown();
    // garbage collection check / read results
    $p->collect(function($checkingTask){
    echo     $checkingTask->val;
    return     $checkingTask->isGarbage();
    });

    ?>
    up
    -5
    fajan
    10 years ago
    Example class to demonstrate usage of Pool/Worker mechanism, also to show a few tricks & hints ;)
    <?php
    class Config extends Threaded{ // shared global object
    protected $val=0, $val2=0;
    protected function     inc(){++$this->val;} // protected synchronizes by-object
    public function inc2(){++$this->val2;} // no synchronization
    }
    class     WorkerClass extends Worker{
    protected static     $worker_id_next = -1;
    protected     $worker_id;
    protected     $config;
    public function     __construct($config){
    $this->worker_id = ++static::$worker_id_next; // static members are not avalable in thread but are in 'main thread'
    $this->config = $config;
    }
    public function     run(){
    global     $config;
    $config = $this->config; // NOTE: setting by reference WON'T work
    global $worker_id;
    $worker_id = $this->worker_id;
    echo     "working context {$worker_id} is created!\n";
    //$this->say_config(); // globally synchronized function.
    }
    protected function     say_config(){ // 'protected' is synchronized by-object so WON'T work between multiple instances
    global $config; // you can use the shared $config object as synchronization source.
    $config->synchronized(function() use (&$config){ // NOTE: you can use Closures here, but if you attach a Closure to a Threaded object it will be destroyed as can't be serialized
    var_dump($config);
    });
    }
    }
    class     Task extends Stackable{ // Stackable still exists, it's just somehow dissappeared from docs (probably by mistake). See older version's docs for more details.
    protected $set;
    public function     __construct($set){
    $this->set = $set;
    }
    public function     run(){
    global     $worker_id;
    echo     "task is running in {$worker_id}!\n";
    usleep(mt_rand(1,100)*100);
    $config = $this->getConfig();
    $val = $config->arr->shift();
    $config->arr[] = $this->set;
    for (    $i = 0 ; $i < 1000; ++$i){
    $config->inc();
    $config->inc2();
    }
    }
    public function     getConfig(){
    global     $config; // WorkerClass set this on thread's scope, can be reused by Tasks for additional asynch data source. (ie: connection pool or taskqueue to demultiplexer)
    return $config;
    }
    }

    $config = new Config;
    $config->arr = new \Threaded();
    $config->arr->merge(array(1,2,3,4,5,6));
    class     PoolClass extends Pool{
    public function     worker_list(){
    if (    $this->workers !== null)
    return     array_keys($this->workers);
    return     null;
    }
    }
    $pool = new PoolClass(3, 'WorkerClass', [$config] );
    $pool->worker_list();
    //$pool->submitTo(0,new Task(-10)); // submitTo DOES NOT try to create worker

    $spammed_id = -1;
    for (    $i = 1; $i <= 100; ++$i){ // add some jobs
    if ($spammed_id == -1 && ($x = $pool->worker_list())!= null && @$x[2]){
    $spammed_id = $x[2];
    echo     "spamming worker {$spammed_id} with lots of tasks from now on\n";
    }
    if (    $spammed_id != -1 && ($i % 5) == 0) // every 5th job is routed to one worker, so it has 20% of the total jobs (with 3 workers it should do ~33%, not it has (33+20)%, so only delegate to worker if you plan to do balancing as well... )
    $pool->submitTo($spammed_id,new Task(10*$i));
    else
    $pool->submit(new Task(10*$i));
    }
    $pool->shutdown();
    var_dump($config); // "val" is exactly 100000, "val2" is probably a bit less
    // also: if you disable the spammer, you'll that the order of the "arr" is random.
    ?>
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