[PHP] 使用 pcntl 库实现PHP多进程

摘要： 最近因项目需要，需要大量同步数据，数据量基数在3000万条左右，因此想到了开启多进程来处理，下面是处理的完整代码，基于laravel 5.1框架。 这是经过实际环境验证过的，所以类似场景可以简单修改下就可使用。

最近因项目需要，需要大量同步数据，数据量基数在3000万条左右，因此想到了开启多进程来处理，下面是处理的完整代码，基于laravel 5.1框架。
这是经过实际环境验证过的，所以类似场景可以简单修改下就可使用。

    /**     * ******数据同步脚本     *     * @author yedonghai     */    namespace App\Console\Commands;    use DB;    use Illuminate\Console\Command;    use App\Services\ZzcService;    class ZzcSyncCommand extends Command    {        /**         * The name and signature of the console command.         *         * @var string         */        protected $signature = 'zzcsync:data';        /**         * The console command description.         *         * @var string         */        protected $description = 'sync zzc apply info';        /**         * Execute the console command.         *         * @return mixed         */        public function handle()        {            $userNum = 6500000;            $workers = 30;            $block = 50000;            $loop = 0;            $flag = 0;            $processIds = [];            do {                $flag = $loop * $workers * $block;                for ($i = 0; $i < $workers; $i++) {                    $minUserId = ($block * $i) + $flag;                    $maxUserId = $block * ($i + 1) + $flag;                    if ($minUserId < $userNum) {                        $processIds[$i] = pcntl_fork();                        switch ($processIds[$i]) {                            case -1 :                                echo "fork failed : {$i} \r\n";                                exit;                            case 0 :                                $this->_userReport($minUserId, $maxUserId);                                exit;                            default :                                break;                        }                    } else {                        break;                    }                }                while(count($processIds) > 0) {                    $mypid = pcntl_waitpid(-1, $status, WNOHANG);                    foreach ($processIds as $key => $pid) {                        if ($mypid == $pid || $mypid == -1) {                            unset($processIds[$key]);                        }                    }                }                $loop++;            } while (empty($processIds) && $flag < $userNum);        }        /**         * 子进程获取指定数据         *         * @param integer  $minUserId  读取区间的下限         * @param integer  $maxUserId  读取区间的上限         *         * @return array         */        private function _userReport($minUserId, $maxUserId)        {            $users = DB::table('users')->leftJoin('user_credits', 'user_credits.user_id', '=', 'users.id')                ->select('users.id', 'users.user_name as mobile', 'users.id_number as pid', 'users.truename as name')                ->where('user_credits.audit_limit', '>', 0)                ->where('users.id', '>=', $minUserId)                ->where('users.id', '<', $maxUserId)                ->get();            foreach ($users as $userObj) {                $userExist = DB::table('zzc_apply')->where('user_id', $userObj->id)->first();                if (!empty((array)$userExist)) {                    continue;                }                $userArr = [];                $userArr['loan_type'] = '消费贷';                $userArr['loan_term'] = '3';                $userArr['loan_purpose'] = '购物';                $userArr['applicant']['name']   = $userObj->name;                $userArr['applicant']['pid']    = $userObj->pid;                $userArr['applicant']['mobile'] = $userObj->mobile;                $user = json_encode($userArr);                $zzcService = new ZzcService();                $zzcService->createNezha($user);            }        }
    }原文链接