php swoole多進程/多線程例子

swoole的多線程其實就是多進程，進程創建太多切換的開銷很大，如果能用上pthreads建議用pthreads，因爲我用的是php7nts版本沒辦法用pthreads

swoole實例如下：

<?php
/**
 * 創建多進程
 */
$worker_num         = 6;        // 默認進程數
$workers             = [];        // 進程保存
$redirect_stdout    = false;    // 重定向輸出  ; 這個參數用途等會我們看效果
for($i = 0; $i < $worker_num; $i++){
    $process = new swoole_process('callback_function', $redirect_stdout);

    // 啓用消息隊列 int $msgkey = 0, int $mode = 2
    $process->useQueue(0, 2);
    $pid = $process->start();

    // 管道寫入內容
    $process->write('index:'.$i);

    $process->push('進程的消息隊列內容');
    // 將每一個進程的句柄存起來
    $workers[$pid] = $process;
}


/**
 * 子進程回調
 * @param  swoole_process $worker [description]
 * @return [type]                 [description]
 */
function callback_function(swoole_process $worker)
{
    $recv = $worker->pop();
    echo "子輸出主內容: {$recv}".PHP_EOL;
    //get guandao content
    $recv = $worker->read();
    $result = doTask();
    
    echo PHP_EOL.$result.'==='.$worker->pid.'==='.$recv;

    $worker->exit(0);
}


/**
 * 監控/回收子進程
 */
while(1){
    $ret = swoole_process::wait();
    if ($ret){// $ret 是個數組 code是進程退出狀態碼，
        $pid = $ret['pid'];
        echo PHP_EOL."Worker Exit, PID=" . $pid . PHP_EOL;
    }else{
        break;
    }
}


/**
 * doTask
 * @return [type] [description]
 */
function doTask()
{
    sleep(2);
    return true;
}