PHP编程中尝试程序并发的几种方式总结

php  /  管理员 发布于 7年前   134

本文大约总结了PHP编程中的五种并发方式：
1.curl_multi_init
文档中说的是 Allows the processing of multiple cURL handles asynchronously. 确实是异步。这里需要理解的是select这个方法，文档中是这么解释的Blocks until there is activity on any of the curl_multi connections.。了解一下常见的异步模型就应该能理解，select, epoll，都很有名

 0);//close the handlescurl_multi_remove_handle($mh, $ch_1);curl_multi_remove_handle($mh, $ch_2);curl_multi_close($mh);

这里我设置的是，select得到结果，就退出循环，并且删除 curl resource, 从而达到取消http请求的目的。

2.swoole_client
swoole_client提供了异步模式，我竟然把这个忘了。这里的sleep方法需要swoole版本大于等于1.7.21, 我还没升到这个版本，所以直接exit也可以。

on("connect", function($cli) {  $req = "GET / HTTP/1.1\r\n  Host: \r\n  Connection: keep-alive\r\n  Cache-Control: no-cache\r\n  Pragma: no-cache\r\n\r\n";  for ($i=0; $i < 3; $i++) {    $cli->send($req);  }});$client->on("receive", function($cli, $data){  echo "Received: ".$data."\n";  exit(0);  $cli->sleep(); // swoole >= 1.7.21});$client->on("error", function($cli){  echo "Connect failed\n";});$client->on("close", function($cli){  echo "Connection close\n";});//发起网络连接$client->connect('183.207.95.145', 80, 1);

3.process
哎，竟然差点忘了 swoole_process, 这里就不用 pcntl 模块了。但是写完发现，这其实也不算是中断请求，而是哪个先到读哪个，忽视后面的返回值。

useQueue();  $pid = $process->start();  $workers[$pid] = $process;}foreach($workers as $pid => $process){  //子进程也会包含此事件  swoole_event_add($process->pipe, function ($pipe) use($process, $lock, &$finished) {    $lock->lock();    if(!$finished){      $finished = true;      $data = $process->read();      echo "RECV: " . $data.PHP_EOL;    }    $lock->unlock();  });}function process(swoole_process $process){  $response = 'http response';  $process->write($response);  echo $process->pid,"\t",$process->callback .PHP_EOL;}for($i = 0; $i < $worker_num; $i++) {  $ret = swoole_process::wait();  $pid = $ret['pid'];  echo "Worker Exit, PID=".$pid.PHP_EOL;}

4.pthreads
编译pthreads模块时，提示php编译时必须打开ZTS, 所以貌似必须 thread safe 版本才能使用. wamp中多php正好是TS的，直接下了个dll, 文档中的说明复制到对应目录，就在win下测试了。 还没完全理解，查到文章说 php 的 pthreads 和 POSIX pthreads是完全不一样的。代码有些烂，还需要多看看文档，体会一下。

url = '';  }  public function run(){}}class Process extends Worker {  private $text = "";  public function __construct($text,$object){    $this->text = $text;    $this->object = $object;  }  public function run(){    while (is_null($this->object->response)){      print " Thread {$this->text} is running\n";      $this->object->response = 'http response';      sleep(1);    }  }}$foo = new Foo();$a = new Process("A",$foo);$a->start();$b = new Process("B",$foo);$b->start();echo $foo->response;

5.yield
以同步方式书写异步代码：

handler = $handler;      $this->socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);     if(!$this->socket) {       die(socket_strerror(socket_last_error())."\n");     }     if (!socket_set_nonblock($this->socket)) {       die(socket_strerror(socket_last_error())."\n");     }     if(!socket_bind($this->socket, "0.0.0.0", 1234)) {       die(socket_strerror(socket_last_error())."\n");     }   }    public function Run() {     while (true) {       $now = microtime(true) * 1000;       foreach ($this->timers as $time => $sockets) {         if ($time > $now) break;         foreach ($sockets as $one) {           list($socket, $coroutine) = $this->tasks[$one];           unset($this->tasks[$one]);           socket_close($socket);           $coroutine->throw(new Exception("Timeout"));         }         unset($this->timers[$time]);       }        $reads = array($this->socket);       foreach ($this->tasks as list($socket)) {         $reads[] = $socket;       }       $writes = NULL;       $excepts= NULL;       if (!socket_select($reads, $writes, $excepts, 0, 1000)) {         continue;       }        foreach ($reads as $one) {         $len = socket_recvfrom($one, $data, 65535, 0, $ip, $port);         if (!$len) {           //echo "socket_recvfrom fail.\n";           continue;         }         if ($one == $this->socket) {           //echo "[Run]request recvfrom succ. data=$data ip=$ip port=$port\n";           $handler = $this->handler;           $coroutine = $handler($one, $data, $len, $ip, $port);           if (!$coroutine) { //echo "[Run]everything is done.\n"; continue;           }           $task = $coroutine->current();           //echo "[Run]AsyncTask recv. data=$task->data ip=$task->ip port=$task->port timeout=$task->timeout\n";           $socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);           if(!$socket) { //echo socket_strerror(socket_last_error())."\n"; $coroutine->throw(new Exception(socket_strerror(socket_last_error()), socket_last_error())); continue;           }           if (!socket_set_nonblock($socket)) { //echo socket_strerror(socket_last_error())."\n"; $coroutine->throw(new Exception(socket_strerror(socket_last_error()), socket_last_error())); continue;           }           socket_sendto($socket, $task->data, $task->len, 0, $task->ip, $task->port);           $deadline = $now + $task->timeout;           $this->tasks[$socket] = [$socket, $coroutine, $deadline];           $this->timers[$deadline][$socket] = $socket;         } else {           //echo "[Run]response recvfrom succ. data=$data ip=$ip port=$port\n";           list($socket, $coroutine, $deadline) = $this->tasks[$one];           unset($this->tasks[$one]);           unset($this->timers[$deadline][$one]);           socket_close($socket);           $coroutine->send(array($data, $len));         }       }     }   } }  class AsyncTask {   public $data;   public $len;   public $ip;   public $port;   public $timeout;    public function __construct($data, $len, $ip, $port, $timeout) {     $this->data = $data;     $this->len = $len;     $this->ip = $ip;     $this->port = $port;     $this->timeout = $timeout;   } }  function AsyncSendRecv($req_buf, $req_len, $ip, $port, $timeout) {   return new AsyncTask($req_buf, $req_len, $ip, $port, $timeout); }  function RequestHandler($socket, $req_buf, $req_len, $ip, $port) {   //echo "[RequestHandler] before yield AsyncTask. REQ=$req_buf\n";   try {     list($rsp_buf, $rsp_len) = (yield AsyncSendRecv($req_buf, $req_len, "127.0.0.1", 2345, 3000));   } catch (Exception $ex) {     $rsp_buf = $ex->getMessage();     $rsp_len = strlen($rsp_buf);     //echo "[Exception]$rsp_buf\n";   }   //echo "[RequestHandler] after yield AsyncTask. RSP=$rsp_buf\n";   socket_sendto($socket, $rsp_buf, $rsp_len, 0, $ip, $port); }  $server = new AsyncServer(RequestHandler); $server->Run();  ?> 

代码解读：

借助PHP内置array能力，实现简单的“超时管理”，以毫秒为精度作为时间分片；
封装AsyncSendRecv接口，调用形如yield AsyncSendRecv()，更加自然；
添加Exception作为错误处理机制，添加ret_code亦可，仅为展示之用。

您可能感兴趣的文章:

• PHP如何解决网站大流量与高并发的问题
• php解决抢购秒杀抽奖等大流量并发入库导致的库存负数的问题
• php并发对MYSQL造成压力的解决方法
• php中并发读写文件冲突的解决方案
• php并发加锁示例
• php多线程并发实现方法
• php session的锁和并发
• PHP接口并发测试的方法(推荐)
• 浅析PHP中Session可能会引起并发问题
• php使用curl并发减少后端访问时间的方法分析
• PHP开发中解决并发问题的几种实现方法分析